Mean platelet volume/platelet count ratio in hepatocellular carcinoma

Mean platelet volume (MPV) has been actively investigated in liver disease such as steatosis, cirrhosis and hepatitis. Recently, MPV/platelet count (PC) ratio has been proposed as a predictor of long-term mortality after myocardial infarction. As PC is known to be decreased in various liver diseases such as cirrhosis, hepatosplenomegaly and malignancy, we planned to evaluate MPV/PC ratio in patients with hepatocellular carcinoma (HCC) in this study. Mean of MPV levels showed significant difference, which were 8.69?fl (range 6.7–12.2?fl) in patients group and 8.02?fl in control group (range 6.7–11.0?fl). In receiver operating characteristic (ROC) curve analysis, the MPV/PC ratio (fl/(10⁹/l)) presented 74.5% of sensitivity and 96.5% of specificity at the criterion?>?0.0491 (area under the curve (AUC)?=?0.884), while MPV alone showed 57.4% of sensitivity and 81.4% of specificity at the criterion?>?8.4?fl. Further studies should evaluate underlying pathogenic mechanisms of MPV/PC ratio difference and various possibilities of this ratio as an indicator of presence of a tumor in HCC.     

Mean platelet volume in patients with subclinical hypothyroidism

Subclinical hypothyroidism (SCH) is frequently encountered in the general population. Since it is generally asymptomatic, these patients are mostly identified through routine screening or evaluation of non-specific symptoms. It has been suggested as a risk factor for cardiovascular disease. On the other hand, mean platelet volume (MPV), which is a determinant of platelet function, is an independent risk factor for cardiovascular disease. The aim of this study was to evaluate MPV values in subclinical hypothyroidic patients when they were subclinical hypothyroidic and became euthyroidic after 12 weeks of levothyroxine replacement therapy. Sixty patients with subclinical hypothyroidism and 78 euthyroid healthy subjects matched for age, gender and body mass index were enrolled in the study. None of the study subject had diabetes, hypertension or dyslipidemia. All the study subjects were evaluated by biochemical and platelet parameters. Subclinical hypothyroidic patients were then reevaluated with the same parameters when they became euthyroid after 12 weeks of levothyroxine treatment. Platelet counts and metabolic parameters, except serum triglyceride and high density lipoprotein cholesterol (HDLC) levels, were similar between the two groups. Serum triglyceride and MPV values were significantly higher (pTG?=?0.007 and pMPV?<?0.001) while HDLC levels were lower (pHDLC?=?0.008) in the subclinical hypothyroidic group. MPV was found to be correlated with only antithyroid peroxidase (anti-TPO) antibody levels (P?<?0.001). MPV values were decreased after subclinical hypothyroidic patients became eythyroid. However, post-treatment MPV values were still higher (p?=?0.035) in the patient group than in control group. These results suggest that subjects with SCH are susceptible to increased platelet activation and increased MPV values which contribute to increased risk of cardiovascular complications.     

Coronary heart disease is associated with mean platelet volume in type 2 diabetic patients

Background: Mean platelet volume (MPV) is an indicator of platelet activation which is a central process in the pathophysiology of coronary heart disease (CHD). The aim of the study was twofold; first to determine whether MPV values is increased in patients with DM, and secondly to evaluate the relation between diabetic complications and MPV. Methods: The study population included 258 patients divided into two groups. Group A composed of 158 type 2 diabetic patients with coexistent coronary artery disease (stenotic lesions of 50%) (78 women, 80 men; mean age 53.9_10.8; mean diabetes duration 13.1_6.0). One hundred subjects (48 women, 52 men; mean age 53.9_11) without type 2 diabetes with normal coronary angiographies were taken as the control group (group B). To evaluate the extension of CHD, Gensini scoring system was used. Results: The MPV was significantly different in the patient group compared to the controls (9.79 ± 1.5 fl vs 8.3 ± 0.9 fl, P<0.001). The existence of CHD was associated with MPV with odds ratio (95% CI) of 2.31 (1.55–4.42, p50.001). Conclusion: We have found that diabetic patients with coronary heart disease have significantly higher MPV values compared to control subjects without diabetes and with angiographically normal coronary arteries.     

Atrial fibrillation is associated with increased mean platelet volume in patients with type 2 diabetes mellitus

Platelet abnormalities in diabetes mellitus (DM) and atrial fibrillation (AF) may underline the etiology of a prothrombotic state in these conditions. Increased mean platelet volume (MPV) is a marker of abnormal platelet function and activation. We aimed to investigate the possible association of chronic AF with MPV in patients who have type 2 DM. Patients who had type 2 DM with either chronic (≥6 months) AF or normal sinus rhythm (NSR) were included in the study. A total of 162 patients (aged 38–89 years) were divided into 2 groups according to the presence of either AF or NSR. Group 1 consisted of 81 diabetic patients with AF, and group 2 consisted of 81 diabetic patients with NSR. The two groups were not significantly different in terms of age, and gender, as well as in hypertension, smoking, history of coronary artery disease, previous cerebrovascular accidents, microalbuminuria, retinopathy, duration of DM, body mass index, hemoglobin A_1c, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride (p?>?0.05 for all variables). Although no significant difference was present between groups concerning platelet count; for patients with AF, MPV was higher compared with patients with NSR (9.0?±?0.2?fl vs. 8.4?±?0.2?fl; p?=?0.001). Furthermore, no significant difference was noted between groups regarding routine medications received by patients. In multivariate logistic regression analysis, MPV was the only variable independently related to AF (OR?=?2.659; 95% CI, 1.286–5.498; p?=?0.008). Consequently, it is concluded that AF is associated with increased MPV in patients with type 2 DM, suggesting the presence of tentatively related processes leading to reciprocal interaction.     

Mean platelet volume/platelet count ratio as a predictor of long-term mortality after non-ST-elevation myocardial infarction

Previous studies reported an association between elevated mean platelet volume (MPV) and post-myocardial infarction mortality. This study explores the association between long-term mortality after non-ST-segment elevation myocardial infarction (NSTEMI) and the peripheral blood platelet indices (i.e., the mean platelet volume (MPV), platelet count, and the MPV/platelet (MPV/P) ratio). Two physicians independently reviewed the data of 619 NSTEMI patients. The blood samples were drawn and analyzed within 1?h of admission, the second, and the last hospital days. Patients were stratified into equal tertiles according to the platelet count, MPV, and MPV/platelet ratio. The primary outcome, 4-year all-cause mortality, was compared among the platelet indices tertile models. According to MPV, platelet count, and MPV/platelet ratio tertile models, there was a trend of higher 4-year mortality for the lower and upper tertiles in comparison to the middle tertiles. However, only the admission MPV/platelet ratio tercile model was statistically significant for predicting the 4-year mortality. The mortality rate of the highest MPV/platelet (48/207 (23%)) and the lowest (41/206 (20%)) tertiles were significantly higher than the middle tertile (19/206 (9%)), p?=?0.0004 by the chi-squared test. After adjusting for Global Registry of Acute Coronary Events, the patients in the combined first and third MPV/P tertiles had higher mortality in reference to those in the middle MPV/P tercile (hazard ratio 1.951, confidence interval 1.032–3.687, and p?<?0.0396). Our novel finding is that the MPV/platelet ratio is superior to the MPV alone in predicting long-term mortality after NSTEMI. We suggest that using this ratio will magnify any existing relationship between platelet indices and mortality post-NSTMI. Further studies are needed to confirm our finding.     

Increased mean platelet volume in primary Raynaud's phenomenon

We hypothesized that mean platelet volume (MPV), a reliable marker of platelet activation, might be elevated in primary Raynaud's phenomenon (PRP) even if there was no thrombotic complication in our subjects. In this retrospective-cohort study, we examined the clinical value of MPV in 200 patients with PRP and 116 clinical controls, and measured MPV and platelet P-selectin (CD62P) in all study participants. We also evaluated the effect of age, gender, and disease duration on these platelet activation markers in PRP. MPV and CD62 positivities were significantly (p?<?0.001) elevated in patients with PRP compared with controls. These differences retained when patients and controls were analyzed according to age, gender, and the disease duration. In logistic regression analysis, MPV (OR: 15.8, 95% CI: 8.14–30.64, p?<?0.001) and CD62P (OR: 11.3, 95% CI: 4.85–26.12, p?<?0.001) were found to be independently associated with PRP. In conclusion, increased MPV is independently related to PRP, and its level was not influenced by age, gender, and the duration of PRP.     

The effect of weight loss on the mean platelet volume in obese patients

Obesity is a chronic metabolic disorder associated with cardiovascular disease and atherosclerosis. Platelet activation and aggregation are central processes in the pathophysiology of cardiovascular disease. Mean platelet volume (MPV), a determinant of platelet activation, is a newly emerging risk marker for atherothrombosis. Our objective was to evaluate the effect of weight loss on the MPV in obese patients. We selected 30 obese women patients and 30 non-obese healthy women subjects. All obese patients took the same content and caloric diet treatment for 3 months. Body mass index (BMI), metabolic parameters and MPV were measured at baseline and after 3 months diet treatment. Before diet treatment, obese group had significantly higher MPV levels than in the non-obese control group (8.18?±?1.09 fl vs. 8.01?±?0.95 fl, p?=?0.004). MPV showed positive correlations with BMI level in the obese group (r?=?0.43, p?=?0.017). BMI significantly decreased after diet treatment (36.2?±?3.2?kg/m² vs. 34.7?±?3.6?kg/m², p?<?0.001), in the obese group. MPV significantly decreased after diet treatment in the obese group (8.18?±?1.09 fl vs. 8.08?±?1.02 fl, p?=?0.013). There was a positive correlation between weight loss and reduction in MPV (r?=?0.41, p?=?0.024). In addition to its well-known positive effects on cardiovascular disease risk, weight loss may also possess significant anti-platelet activation properties that can contribute its antiatherogenic effects in obese patients.     

The relationship between mean platelet volume and albuminuria in patients with type 2 diabetes mellitus

Background&aimMean platelet volume (MPV) is suggested as a marker of platelet reactivity and tendency for thrombosis and microvascular complications like albuminuria in patients with type 2 DM. We aimed to measure the MPV in patients with type 2 DM and its correlation with albuminuria, body mass index (BMI), duration of DM, hypertension (HTN), stroke, ischemic heart disease (IHD), and HbA1c level.MethodsA cross sectional study included 100 patients with type 2 DM ≥ 18 y of both genders who were randomly selected from the medical units of Baghdad Teaching Hospital. After taking verbal consents; MPV was measured&correlated with aimed variables. Diabetics with HbA1c ≤ 7% were considered as having adequate control while those with (HbA1c) > 7% as having poor control. Albumin creatinine ratio (ACR) in urine was measured and classified into normal, moderately and severely increased. Odds ratios with 95% CI were calculated and P ≤ 0.05 was considered as statistically significant.ResultsThe mean MPV was 7.7 fl ± 1.2. Regarding ACR, 42% had normal level, 37% with moderately increased and 21% had severely increased level. Regarding HbA1c, 68% were having poorly controlled DM. Mean platelets’ count and MPV were higher in the uncontrolled group with a statistically significant association. There was a statistically significant positive correlation between MPV and albuminuria, duration of DM, HTN, IHD, Stroke, BMI, HbA1c, and platelets count.ConclusionsThe mean MPV was statistically significantly higher in the uncontrolled DM group and there was a statistically significant positive correlation between MPV and albuminuria.     

The effects of continuous positive airway pressure therapy on mean platelet volume in patients with obstructive sleep apnea

Previous studies have reported increased platelet activation and aggregation in patients with obstructive sleep apnea (OSA). Continuous positive airway pressure (CPAP) treatment has been shown to decrease platelet activation. We aimed to study the effects of nasal CPAP therapy has on MPV values in patients with severe OSA. Thirty-one patients (21 men; mean age 53.8?±?9.2 years) with severe OSA (AHI?>?30 events/hour) constituted the study group. An age, gender and body mass index (BMI) matched control group was composed 25 subjects (14 men; mean age 49.6?±?8.5 years) without OSA (AHI?<?5 events/hour). We measured MPV values in patients with severe OSA and control subjects and we measured MPV values after 6 months of CPAP therapy in severe OS patients. The median (IQR) MPV values were significantly higher in patients with severe OSA than in control group (8.5 [8.3–9.1] vs. 8.3 [7.5–8.8] fL; p?=?0.03). The platelet counts were significantly lower in patients with severe OSA than in control group (217.8?±?45.9 vs. 265.4?±?64.0?×?10⁹/L; p?=?0.002). The six months of CPAP therapy caused significant reductions in median (IQR) MPV values in patients with severe OSA (8.5 [8.3–9.1] to 7.9 [7.4–8.2] fL; p?<?0.001). Six months of CPAP therapy caused significant increase in platelet counts when compared with baseline values (217.8?±?45.9 to 233.7?±?60.6?×?10⁹/L; p?<?0.001). We have found that the MPV values of patients with severe OSA were significantly higher than those of the control subjects and 6 months CPAP therapy caused significant reductions in the MPV values in patients with severe OSA.     

New roles for mean platelet volume measurement in the clinical practice?

Several hundreds of studies recently investigated mean platelet volume (MPV) as measured by electronic cell counters in a wide variety of acquired diseases, and most of them found that platelet size was significantly increased with respect to healthy subjects. On this basis, it has been suggested that MPV can be used for diagnostic purposes. Moreover, investigation of subjects with arterial thrombosis not only revealed that their platelets were larger than those of controls, but also found that a high MPV predicted poor prognosis. Despite the large amount of available data, the pathogenesis of increased platelet size in these conditions is unclear. In particular, we do not know whether the increased platelet size is the cause or the consequence of thrombosis. Differences in MPV between patients and controls are usually very small and they reach the statistical significance because of the large number of investigated patients and the standardized methodology for MPV measurement. In real life, the wide variability of MPV possibly due to platelet count, sex, age, and ethnicity, as well as the very poor standardization of the methodologies used for MPV measurement, makes it impossible to decide whether an individual patient has normal or instead slightly increased MPV. So, MPV has presently no role in making diagnosis and defining prognosis in any acquired illness.     

Mean platelet volume: Association with adverse neonatal outcome

The aim of the study was to investigate on a possible association between maternal mean platelet volume (MPV) and oxygen-metabolic changes in pregnancies affected by altered maternal-fetal Doppler velocimetry. We considered the altered maternal-fetal Doppler velocimetry group (n?=?57) pregnant women admitted to our Institution for a pregnancy complication associated to the event Pre-eclampsia (PE) and intrauterine growth retardation (IUGR), with altered Doppler velocimetry in the umbilical artery (?UA) (high pulsatility index, absence or reverse end diastolic flow (ARED), blood flow cephalisation) and/or bilateral increased resistance in uterine arteries. Out of these cases, 25 pregnancies were complicated by PE and 32 pregnancies were complicated by IUGR. We included 145 normotensive third trimester pregnant women as a normal maternal-fetal Doppler velocimetry control group. From all women, 20?ml of whole venous blood was obtained from the antecubital vein soon after Doppler velocimetry evaluation. MPV was significantly higher in women with abnormal Doppler velocimetry compared to those with normal Doppler velocimetry (8.0?fl [7.0–8.7] vs. 9.1?fl [8.0–10.6], <0.001. Values are median [interquartiles]). We performed a ROC curve in order to find an MPV cut-off able to predict an uneventful event in Doppler velocimetry compromised fetuses (neonatal O₂ support?>?48?hrs or intubation and/or pH?<?7.2 at umbilical blood gas analysis (UBGA)). An MPV?≥?10?fl was significantly related to the former diagnostic endpoints compared to that of non-compromised fetuses (sensitivity: 45%, specificity: 89.7%, 95 CI: 18.8–66, p?<?0.01). Our study suggests that pregnancies affected by Doppler velocimetry alterations, an MPV value?≥?10?fl may be associated with severe oxygen support and/or low UA ph at birth.     

Diagnostic and prognostic roles of the mean platelet volume in malignant tumors: a systematic review and meta-analysis

The aim of this study was to elucidate the diagnostic and prognostic roles of the mean platelet volume (MPV) in various malignant tumors through a systematic review and meta-analysis. The current study included 2,053 patients and 1,396 healthy subjects in 18 eligible studies. We performed a meta-analysis of MPV levels and the mean difference between healthy subjects and pre- and post-treatment patients. Subgroup analysis was conducted based on specific organs and platelet counts. In addition, the correlation between MPV and survival was investigated. The pooled MPVs of healthy subjects, pre-treatment, and post-treatment patients were 8.428 fL (95% confidence interval [CI] 8.118–8.738), 8.831 fL (95% CI 8.582–9.087), and 8.521 fL (95% CI 8.162–8.880), respectively. The mean difference in MPV between healthy subjects and pre-treatment patients was 0.502 (95% CI 0.285–0.719, P < 0.001). However, in lung cancer, the mean difference between pre-treatment patients and healthy subjects was ?0.352 (95% CI ?0.763–0.060, P = 0.094). The pooled MPV of post-treatment patients was significantly decreased compared to pre-treatment patients. There was no correlation between MPV and disease-free survival rate (hazard ratio 1.033, 95% CI 0.369–2.895). Our results showed that the MPV level was significantly higher in malignant tumors than in healthy subjects and was decreased after treatment. Further cumulative studies will be required before MPV levels can be applied for screening malignant tumors and predicting prognosis.     

Hypertension is an independent predictor of mean platelet volume in patients with acute ischaemic stroke

Introduction: Mean platelet volume (MPV) was shown to be significantly increased in patients with acute ischaemic stroke, especially in non‐lacunar strokes. Moreover, some studies concluded that increased MPV is related to poor functional outcome after ischaemic stroke, although this association is still controversial. However, the determinants of MPV in patients with acute ischaemic stroke have never been investigated. Subjects and methods: We recorded the main demographic, clinical and laboratory data of consecutive patients with acute (admitted within 24 h after stroke onset) ischaemic stroke admitted in our Neurology Service between January 2003 and December 2008. MPV was generated at admission by the Sysmex XE‐2100 automated cell counter (Sysmex Corporation, Kobe, Japan) from ethylenediaminetetraacetic acid blood samples stored at room temperature until measurement. The association of these parameters with MPV was investigated in univariate and multivariate analysis. Results: A total of 636 patients was included in our study. The median MPV was 10.4 ± 0.82 fL. In univariate analysis, glucose (β= 0.03, P= 0.05), serum creatinine (β= 0.002, P= 0.02), haemoglobin (β= 0.009, P < 0.001), platelet count (β=?0.002, P < 0.001) and history of arterial hypertension (β= 0.21, P= 0.005) were found to be significantly associated with MPV. In multivariate robust regression analysis, only hypertension and platelet count remained as independent determinants of MPV. Conclusions: In patients with acute ischaemic stroke, platelet count and history of hypertension are the only determinants of MPV.     

An overlooked indicator of disease activity in ulcerative colitis: Mean platelet volume

Many non-invasive tests have been studied for diagnosis and determining the activation degree of inflammatory bowel disease (IBD). Nevertheless, an ideal test has not been found yet. Mean platelet volume (MPV) is influenced by the inflammation. In a few study, decreased platelet volume have been reported in IBD. The aim of this study is to determine whether platelet volume would be useful in ulcerative colitis (UC) activity. Additionally we have analyzed overall accuracy of MPV in disease activity and compared with other inflammatory markers. A total of 61 UC patients (male/female : 41/20), and 27 healthy subjects (male/female : 18/9) were enrolled into the study. For all subjects following tests were performed; ESR, CRP, white blood cell count and mean platelet volume. A statistically significant decrease in MPV was noted in patients with UC (8.29 ± 1.02fL) compared with healthy controls (8.65 ± 0.79 fL). MPV of active UC (8.06 ± 1.19 fL) patients were significantly lower than that of inactive UC (8.45 ± 0.87 fL). Overall accuracy of MPV in determination of active UC was 71% (with sensitivity 67%, specificity 73%). A negative correlation was found between MPV and endoscopic activity index (r : -0.358 p : 0.005). In UC, MPV did not correlate with ESR, CRP and white blood cell. Our study showed that MPV reduced in UC, particularly in patients with active UC. Decreased MPV may be an indicator for increased disease activity in patients with UC.     

Mean platelet volume in children with familial Mediterranean fever

Familial Mediterranean fever (FMF) is the most common inherited periodic fever syndrome characterized by recurrent episodes of serositis. Recently, a few studies have suggested that FMF is related to increased risk of atherosclerosis. Mean platelet volume (MPV) is a marker of platelet activation. Larger platelets are associated with increased atherosclerosis risk. The aim of the study is to evaluate levels of MPV in pediatric FMF patients during and between attacks. The study consisted of 48 patients during an attack (group 1), 63 patients in attack-free period (at least 2 weeks after an attack, group 2), and 49 healthy controls (group 3). Erythrocyte sedimentation rate, C-reactive protein, white blood cell count, platelet count (PLT), and MPV levels were retrospectively recorded from the computerized patient database. Mean platelet volume was significantly lower in FMF patients during attack than in attack-free period (p = 0.00); however, there was no difference among attack-free patients and healthy controls (p = 0.38). The mean platelet counts of FMF patients during attack were higher than the healthy controls (p = 0.02). There was an inverse correlation between MPV and mean PLT in the attack-free period (r = −446, p = 0.01). This study suggests that an early atherosclerosis marker, MPV, is not elevated in pediatric FMF patients on colchicine treatment.     

Mean platelet volume in acute rheumatic fever

Acute rheumatic fever (ARF) is still an endemic disease, especially among school-aged children in developing countries. Mean platelet volume (MPV), which is commonly used as a measure of platelet size, indicates the rate of platelet production and platelet activation. We aimed to investigate MPV in children with ARF. The study population consisted of 40 children with ARF (32 patients with carditis and 8 patients without carditis) and 40 healthy control subjects. White blood cell (WBC) and platelet counts were significantly higher and MPV values were significantly lower in patients with ARF during the acute stage when compared to controls. Erythrocyte sedimentation rate (ESR) and C-reactive protein values significantly decreased in patients with ARF after the treatment when compared to baseline, whereas MPV values increased. MPV values were negatively correlated with ESR and WBC, and platelet counts. In conclusion, during the acute stage of ARF, MPV values were lower when compared to controls.     

Association between mean platelet volume and autonomic nervous system functions: Increased mean platelet volume reflects sympathetic overactivity

BACKGROUND:

Increased mean platelet volume (MPV) may reflect increased platelet activation or increased numbers of large, hyperaggregable platelets, and is accepted as an independent coronary risk factor. The adrenergic system has effects on platelet activation and thrombocytopoiesis.

OBJECTIVE:

To assess the effects of autonomic nervous system activity on MPV in patients with acute myocardial infarction (MI).

METHODS AND RESULTS:

Forty-seven patients with acute anterior MI were compared with 32 patients with healthy coronary arteries. All patients underwent heart rate (HR) variability analysis using 24 h Holter monitoring. Blood samples were taken for MPV measurements twice a day (day- and nighttime) during Holter monitoring. Mean HR, low frequency band of HR variability power spectrum to high frequency band of HR variability power spectrum (LF:HF) ratio, LF and MPV were higher in patients with anterior MI than in the control group. SD of all NN (RR) intervals, root mean square of successive differences, number of NN intervals that differed by more than 50 ms from the adjacent interval divided by the total number of all NN intervals, HF bands and platelet counts were lower in the patients with anterior MI than in the control group. Daytime LF bands, LF:HF ratio and MPV were significantly higher, and HF bands were significantly lower than the nighttime values for both groups. The differences in daytime and nighttime measurements were more significant in the patients with acute MI than in the control group. Pearson’s correlation analysis showed that MPV was positively correlated with ventricle score, degree of left anterior descending artery stenosis, mean HR, LF bands and LF:HF ratio; and negatively correlated with the SD of all NN intervals, HF bands and platelet count. Multivariate analysis revealed that MPV was significantly affected by ventricle score and the LF:HF ratio.

CONCLUSIONS:

MPV was significantly higher in the patients with acute MI. In both groups, MPV showed great daytime and nighttime variation, which can be attributed to alterations in the autonomic nervous system. The authors suggest that the prognostic role of increased MPV in patients with acute MI is closely associated with increased sympathetic activity and decreased HR variability.     

Mean platelet volume as an inflammatory marker in patients with severe periodontitis

Periodontitis has become the leading cause of tooth loss in adults, and the host’s immunologic and inflammatory response to the bacteria can lead to periodontal destruction. In patients with periodontitis, platelets possess an increased activation status compared with platelets from healthy controls. Mean platelet volume (MPV) has been considered an important index of platelet activity and an inflammatory marker in many infectious diseases. The present study investigated the relationship between MPV and disease activity in subjects with severe periodontitis. Forty-five patients with periodontitis and 45 age and sex-matched healthy subjects were enrolled into the study. All subjects received periodontal and hematological examinations. The periodontitis patients were administered active periodontal treatment (APT). At baseline, a statistically significant decrease in MPV was noted in patients with periodontitis (9.73?±?1.06 fL) compared with healthy controls (10.24?±?1.07 fL). At 1 month post-APT, MPV was substantially increased (10.11?±?1.04 fL). Positive correlation was found between increase of MPV and decrease of periodontal probing depth after treatment(r?=?0.377; p?=?0.014). In conclusion, the decrease of MPV was related to the severe periodontal inflammation, and the value inversed shift after APT. MPV might reflect the disease activity of periodontitis.     

Reversible and irreversible binding of fibrinogen to platelets

Abstract

Atrial fibrillation (AF) is the most common sustained arrhythmia and associated with adverse outcomes and increased risk for thromboembolic events. Warfarin is still the most extensively prescribed oral anticoagulant in AF to prevent ischemic complications. We aimed to determine the differences at platelet indices with warfarin usage layered by International Normalized Ratio (INR). A total of 250 patients with permanent non-valvular AF (mean age 70.2?±?9.1; 153 female) were divided into two groups. Group 1 included 125 patients whose INR is between 2.0 and 3.0 (called as “effective”) and Group 2 included 125 patients whose INR is <2.0 (called as “ineffective”). Also 123 age- and sex-matched individuals in sinus rhythm enrolled as control group (Group 3). After physical and echocardiographic examination, complete blood counts and INR were studied. There was no statistically significant difference in age, sex, co-morbidities and medications, also hemoglobin, white blood cell and platelet counts among the groups. The CHA₂DS₂-VASc scores were similar between Groups 1 and 2. The mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT) were significantly higher in Group 2 than Groups 1 and 3 and similar between Groups 1 and 3. MPV was positively correlated with PDW and PCT and also inversely correlated with INR value and platelet count. On multivariate logistic regression analysis, MPV, PDW and PCT were independent predictors of ineffectiveness of INR. The results of this study showed that MPV, PDW and PCT are increased in patients with non-valvular AF without effective warfarin treatment. Warfarin usage adjusted by INR is associated with lower values of these platelet indices, even lower as the values of subjects in sinus rhythm. MPV, PDW and PCT are independent predictors of INR ineffectiveness and seem to be useful parameters for monitoring the effectiveness of warfarin treatment.     

The effect of aspirin on mean platelet volume in patients with paroxysmal atrial fibrillation

Aspirin is one of the preferred therapies in the primary prevention of ischemic stroke in paroxysmal atrial fibrillation (PAF). Mean platelet volume (MPV) is a marker of platelet size and activation. Increased MPV reflects active and large platelets. The present observational study was designed to investigate whether aspirin treatment does affect MPV levels in patients with PAF. The study included 101 patients who were detected to have PAF by 24-hour Holter monitoring and divided into two groups based on aspirin treatment [ASA (+) and ASA (?)]. MPV was measured. Patients with aortic and mitral stenosis, hyperthyroidism, hypothyroidism, malignancy, infection, and pregnancy were excluded from the study. Of the 101 patients, 50 had no antiplatelet therapy and 51 had daily aspirin (100?mg) intake. Mean age of the patients was 66?±?10 years and 35 (68%) were male in ASA (+) group. There was no difference in median levels of MPV (9.9 vs. 10.2?fl, respectively; p?=?0.9) between groups. Both uni- and multivariate logistic regression analyses did not show an association between MPV and ASA use. Our results indicate that MPV as a predictive marker of platelet size and activity is not affected by aspirin use in patients with PAF.