The association between exposure to a rear-end collision and future neck or shoulder pain: a cohort study

Neck pain is the most frequently reported feature in connection with whiplash injury, but it is also a common complaint in the general population. Therefore it is crucial to include an unexposed comparison group when evaluating the association between neck pain and a previous motor vehicle crash (MVC). To determine whether exposure to a rear-end collision, without or with whiplash injury, is associated with future neck or shoulder pain, a cohort study was conducted. The study population consisted of persons covered by traffic insurance at one of the largest insurance companies in Sweden. Claim reports were collected from the period November 1987 to April 1988. Drivers exposed to a rear-end collision were divided into two subgroups, without reported whiplash injury (n = 204) and with reported whiplash injury (n = 232). Two comparison groups, unexposed to MVCs, consisting of 1599 and 2089 persons, were selected with consideration taken to the age and gender distribution in the exposed subgroups. A questionnaire concerning neck or shoulder pain and other subjective health complaints was mailed to all the study subjects at follow-up in 1994, 7 years after the rear-end collision. The relative risk of neck or shoulder pain at follow-up was 1.3 (95% CI 0.8-2.0) in the exposed subjects without whiplash injury compared with the unexposed. The corresponding relative risk in subjects with whiplash injury was 2.7 (95% CI 2.1-3. 5). We conclude that there is no increased risk of future neck or shoulder pain in drivers who did not report whiplash injury in connection with a rear-end collision 7 years earlier. In drivers with reported whiplash injury, the risk of neck or shoulder pain 7 years after the collision was increased nearly three-fold compared with that in unexposed subjects.     

Occupant- and crash-related factors associated with the risk of whiplash injury

PURPOSE: Given that a motor vehicle crash (MVC) had occurred, to evaluate whether occupant- and crash-related factors, such as age, gender, seating position and type of MVC are associated with the risk of whiplash injury. METHODS: A study of occupants in cars covered by motor insurance at one of the largest insurance companies in Sweden, was undertaken during a one-year period. The study population comprised all occupants in cars exposed to an MVC in which at least one occupant was injured (n = 7120). Adjusted estimates of the relative risk of whiplash injury, associated with the different factors, were calculated by means of binomial regression analysis. RESULTS: Considering different MVCs, rear-end collisions were associated with the highest relative risk of whiplash injury when compared with side impacts (1.82; 95% CI 1.68-1.96), while drivers showed the strongest association with respect to seating position when compared with passengers in the rear seat (1.78; 95% CI 1.60-1.97). Females had a somewhat higher relative risk of whiplash injury than males (1.20; 95% CI 1.16-1.25). Regarding age, the relative risk was moderately increased across the different age groups when compared with the oldest age group. No interaction was observed on the additive scale. CONCLUSIONS: Given that an MVC had occurred, subjects exposed to a rear-end collision and drivers had a substantial increased risk of whiplash injury, while age and gender were of minor importance.     

Long-term labour-market performance of whiplash claimants

A whiplash is a sudden acceleration–deceleration of the neck and head, typically associated with a rear-end car collision that may produce injuries in the soft tissue. Often there are no objective signs or symptoms of injury, and diagnosing lasting whiplash-associated disorders (WAD) is difficult, in particular for individuals with mild or moderate injuries. This leaves a scope for compensation-seeking behaviour. The medical literature disagrees on the importance of this explanation. In this paper we trace the long-term earnings of a group of Danish individuals with mild to moderate injuries claiming compensation for having permanently lost earnings capacity and investigate if they return to their full pre-whiplash earnings when the insurance claim has been assessed. We find that about half of the claimants, those not granted compensation, return to an earnings level comparable with their pre-whiplash earnings suggesting that these individuals do not have chronic WAD in the sense that their earnings capacity is reduced. The other half, those granted compensation, experience persistent reductions in earnings relative to the case where they had not been exposed to a whiplash, even when they have a strong financial incentive to not reduce earnings. This suggests that moderate injuries tend to be chronic, and that compensation-seeking behaviour is not the main explanation for this group. We find that claimants with chronic WADs used more health care in the year prior to the whiplash than claimants with non-chronic cases. This suggests that lower initial health capital increases the risk that a whiplash causes persistent WAD.     

The association between neck pain intensity, physical functioning, depressive symptomatology and time-to-claim-closure after whiplash

Time-to-claim-closure is a common outcome in cohort studies of whiplash injuries. However, its relationship to health recovery is unknown. We investigated the association between neck pain, physical functioning, depressive symptomatology and time-to-claim-closure in a Saskatchewan cohort of 5398 whiplash claimants in 1994-1995. Participants were surveyed five times over 1 year. In 1995, the insurance system changed from tort to no-fault, eliminating compensation for pain and suffering. Under tort, a 10-point increase in pain reduced the claim-closure rate by 13-24% while a 10-point increase in physical functioning increased it by 17%. Depressive symptomatology reduced the claim-closure rate by 37%. Under no-fault, a 10-point increase in pain reduced the claim-closure rate by 18% while a 10-point increase in physical functioning increased it by 10-35%. The presence of depressive symptomatology reduced the claim-closure rate by 36%. The results suggests lower pain, better function and the absence of depressive symptoms are strongly associated with faster time-to-claim-closure and recovery after whiplash, independent of the insurance system.     

Association between body mass index and recovery from whiplash injuries: a cohort study

It is hypothesized that excess weight is a risk factor for delayed recovery from neck pain, such as from whiplash injuries. However, the association between obesity and recovery from whiplash injury has not been studied. The authors examined the association between body mass index and time to recovery from whiplash injuries in a population-based cohort study of traffic injuries in Saskatchewan, Canada. The cohort included 4,395 individuals who made an insurance claim to Saskatchewan Government Insurance and were treated for whiplash injury between July 1, 1994, and December 31, 1995. Of those, 87.7% had recovered by November 1, 1997. No association was found between baseline body mass index and time to recovery. Compared with individuals with normal weight, those who were underweight (hazard rate ratio = 0.88, 95% confidence interval: 0.73, 1.06), overweight (hazard rate ratio = 1.01, 95% confidence interval: 0.94, 1.09), and obese (hazard rate ratio = 0.99, 95% confidence interval: 0.90, 1.08) had similar rates of recovery, even after adjustment for other factors. The results do not support the hypothesis that individuals who are overweight or obese have a worse prognosis for whiplash.     

Sprain of the neck: Quality of life and psychological functioning. A 4-year retrospective study

Aim of the study was to analyse quality of life and psychological functioning in patients with sprain of the neck, to analyse the relationship between complaints, quality of life, psychological functioning and personality factors, and to analyse the profile of patients with whiplash associated disorders (WAD), 4 years after trauma. From the University Hospital Groningen 193 patients with the diagnose sprain of the neck filled out a questionnaire. Of this group 100 subjects did not have complaints before the accident and were therefore at risk for the development of complaints as a result of sprain of the neck. Quality of life and psychological functioning were assessed using the RAND-36 and the SCL-90, respectively. Personality was assessed by means of the Dutch Personality Questionnaire. Of the group at risk (56% women and 44% men, mean age: 33.9, SD: 14.6) quality of life was significantly worse in subjects with complaints (mean: 78.4, SD: 15.5) compared to subjects without complaints (mean: 87.5, SD: 8.7). Psychological functioning did not differ significantly between the group with complaints compared to group without complaints. Personality did not differ between the groups. Personality and complaints together were significantly related to quality of life (r: 0.77) and psychological functioning (r: 0.85). No specific profile of WAD patients was found. In conclusion, personality and complaints influence quality of life and psychological functioning to a considerable extent.     

Tragedy of conducting a clinical trial; generic alert system needed

Stopping a clinical trial without reaching the final objective is not the ideal outcome any researcher wants; sometimes ceasing is inevitable. Due to marginal inclusion of patients we were forced to cease our randomized clinical trial on the effectiveness of proprioceptive training on the development of chronic whiplash complaints a year after the start. Although incidence figures demonstrate that recruitment of the planned number of whiplash patients would be easily feasible, we were unable to enroll the amount of subjects. Several motives can be proposed that would have prevented this obliged halting from happening. Other studies also report impracticability of the planned number of whiplash injury patients.     

Whiplash, chronic neck pain, and zygapophyseal joint disorders. A selective review

Recent research on whiplash injury has challenged the long-held view of what causes chronic neck pain in car accident victims. Although it was previously thought to result from residual scarring of muscles and ligaments, such pain is now understood to be caused by zygapophyseal-joint damage, which produces no objective findings on radiologic testing and often none on physical examination. Chronic pain from a whiplash injury can be reliably diagnosed and effectively treated in most patients by z-joint testing and radiofrequency blocks.     

Respiratory symptoms and pathophysiological effects of occupational exposure to formaldehyde and wood dust

The hazards of exposure to formaldehyde have been widely discussed in recent years on account of the health complaints of exposed persons. Both domestic and occupational exposure to formaldehyde is common. In the present study the effects of formaldehyde alone and in combination with wood dust, another nasal irritant, on the upper and lower respiratory tract have been investigated. The effects were correlated with the duration and degree of exposure. Discomfort from both the upper and lower airways was more frequent in the exposed group than in the unexposed group. Nasal obstruction among the exposed subjects in general could not be detected by rhinomanometric measurements, but, for the group exposed to formaldehyde alone and with a history of nasal blocking, there was significant nasal mucosal swelling. The nasal mucociliary clearance was significantly delayed, and the sense of smell was significantly reduced in the exposed groups when they were compared with the referents. Spirometry showed a significantly decreased forced vital capacity in the exposed groups. There were no signs in this investigation that duration of exposure or level of exposure to formaldehyde would have any influence on the severity of symptoms or the impairment of physiological conditions.     

Health insurance and subjective health status: data from the 1987 National Medical Expenditure survey.

OBJECTIVES. The relationship between health insurance and subjective health status was investigated. It was hypothesized that persons without health insurance would have lower levels of subjective health status than those with health insurance and that this relationship would hold for both poor and nonpoor persons. METHODS. Data from the 1987 National Medical Expenditure Survey were analyzed to examine the relationship between health insurance and self-reported health status. The analysis controlled for sociodemographic and attitudinal variables and medical conditions. RESULTS. Persons without health insurance had significantly lower levels of subjective health status than did persons with insurance. This adverse effect persisted after adjustments were made for the effects of age, sex, race, income, attitude toward the value of medical care and health insurance, and medical conditions. The detrimental effect of lacking health insurance on subjective health status was present for persons at all income levels and was greater than the effect on subjective health status found for 2 of the 11 reported medical conditions. CONCLUSIONS. Lacking health insurance is associated with clinically significant lower levels of subjective health status in both poor and non-poor persons.     

Assessment of somatic complaints in environmental health

In patients attributing their health complaints to environmental factors (EnvPat) evidence based medical diagnostics usually do not confirm environmental and somatic causes of symptoms. Many symptoms remain unexplained. Aim of the study was the systematic assessment of medically unexplained physical symptoms (MUPS) in EnvPat and comparison to symptom rates reported by subjects of an environmental study exposed to environmental odors (EnvExp). This specific exposure was chosen, as odors are associated by an unclear mechanism with physical symptoms. By this we aimed to enlighten the open question as to likeliness that MUPS of EnvPat are caused by hitherto unrevealed environmental exposures or result from somatization. MUPS were measured with SOMS-2 in EnvPat n=92, patients presenting in a university environmental outpatients clinic, and different study groups exposed to environmental odors (EnvExp). These were: (1) subjects exposed to annoying odors and medically relevant concentrations of bioaerosols, such as airborne microorganisms (EnvExp-1, n=74), and (2) subjects exposed to odors alone (EnvExp-2, n=282) as well as unexposed controls (Controls, n=235). Logistic regression and analysis of variance were applied to analyze rates of single complaints and the sum index of complaints (SOMS-CoIx). In EnvPat rates of MUPS were highest - significant (p<0.05) adjusted OR in 23 of 25 MUPS compared to controls - and highest SOMS-CoIx (mean 15.3 (S.D. +/-9.3). Rates of MUPS were lower in environmentally exposed subjects with difference in the two strata: while EnvExp-1 differed in several complaints, i.e., nausea and SOMS-CoIx (mean 7.2, S.D. +/-6.9) from controls (p<0.05), EnvExp-2 (SOMS-CoIx mean 4.8, S.D. +/-5.2) showed relevant differences only in two single complaints and not in the SOMS-CoIx from controls, SOMS-CoIx mean 3.9, S.D. +/-5.0. This remained when adjusting for age, gender, and school education. Rates of MUPS in environmental patients were clearly higher than in subjects with actual environmental exposure, making it unlikely that their symptoms are due to undetected environmental factors. MUPS of EnvPat show similarities to psychosomatic patients. In the environmental survey symptom assessment by SOMS-2 was sensitive to different environmental scenarios, i.e., higher rates of physical complaints were only found in subjects with hazardous residential bioaerosols pollution as well as an annoying odor exposure and interestingly not in subjects exposed to annoying odors alone. This underlines that questionnaire data of somatic complaints need to be interpreted on the basis of exposure assessment in order to unjustly attribute health complaints to annoyance.     

Hypospadias in sons of women exposed to diethylstilbestrol in utero

BACKGROUND: Diethylstilbestrol (DES) is a synthetic estrogen that was widely prescribed to pregnant women before 1971. DES increases the risk of breast cancer in women who took the drug and the risk of reproductive tract abnormalities in their offspring. Dutch investigators have reported a 20-fold increase in risk of hypospadias among sons of women who were exposed to DES in utero. We assessed this relation in data from an ongoing study of DES-exposed persons. METHODS: Several U.S. cohorts of women with documented exposure in utero to DES have been followed by mailed questionnaires since the 1970s. Comparison subjects are unexposed women of the same ages. In 1997, participants were asked about congenital abnormalities in their children. We calculated prevalence odds ratios for the risk of hypospadias in sons of exposed mothers relative to sons of unexposed mothers using generalized estimating equations to adjust for multiple sons per mother and controlling for maternal age at the son's birth. RESULTS: We obtained data from 3916 exposed and 1746 unexposed women. These women reported a total of 13 liveborn sons with hypospadias (10 exposed, 3 unexposed). The prevalence odds ratio for risk of hypospadias among the exposed was 1.7 (95% confidence interval = 0.4-6.8). CONCLUSIONS: Our findings do not support a greatly increased risk of hypospadias among the sons of women exposed to DES in utero, as has been previously reported.     

Comparison of self-reported diagnosis of connective tissue disease with medical records in female health professionals: the Women's Health Cohort Study.

To compare self-report of connective tissue disease (CTD) with medical records, subjects were selected from 395,543 female health professionals with and without breast implants who reported CTD on mailed questionnaires from 1992 to 1995. The authors identified 220 women with breast implants (exposed) who self-reported CTD and a random sample of 879 women without breast implants (unexposed) who also self-reported CTD, matched by age and date of diagnosis. Medical records were reviewed using classification criteria from the American College of Rheumatology or other published criteria. After up to three requests and a telephone call, 27.7% of the women provided consent for medical record review. Exposed women appeared somewhat more likely (33.2% vs. 26.3%, p = 0.04) to provide consent. Using medical record reviews for 90% of the women who provided consent, confirmation rates of definite CTD were similar among the exposed and unexposed (22.7% vs. 24.0%, p = 0.83). This study demonstrates the difficulty of obtaining consent for medical record review of CTD reported to have occurred years ago in women with and without breast implants. Confirmation rates were low but were similar in exposed and unexposed. Despite the fact that the study had low participation rates, the data suggest that relative risk estimates for any definite CTD among women with breast implants compared with women without breast implants would be similar in analyses of self-reported or medical record-confirmed cases.     

High incidence and recurrence of shoulder and neck pain in nursing home employees was demonstrated during a 2-year follow-up

OBJECTIVE: This study describes the course of shoulder and neck complaints in a working population over time. STUDY DESIGN AND SETTING: Questionnaires were administered on neck and shoulder complaints over 3 consecutive years. RESULTS: We observed 12-month incidence rates for neck and shoulder complaints of 16% to 18%, 12-month prevalence rates roughly twice as high, and 12-month recurrence rates approximately twice the prevalence rates. Each year, medical care was sought by 21% to 38% of the subjects with neck or shoulder pain, and 13% to 21% were absent from work. Although at the population level the occurrence of neck and shoulder complaints remained constant, the course of complaints within individuals demonstrated a strong episodic nature of neck and shoulder pain. Results from this study suggest that neck and shoulder complaints for most subjects run a recurrent course characterized by a strong variation in occurrence and a self-limiting course. CONCLUSION: These findings suggest that clinical trials should have a sufficiently long follow-up period to demonstrate sustainability of the therapeutic results.     

Risk factors for musculoskeletal disorders among nursing personnel in Greek hospitals

OBJECTIVES: To investigate the relationships between physical, psychosocial, and individual characteristics and different endpoints of musculoskeletal complaints of the lower back, neck and shoulders. METHODS: In this cross-sectional study a questionnaire survey was carried out among 351 nursing personnel (response 84%) in six general hospitals in Athens, Greece. A questionnaire was used on physical and psychosocial workload, need for recovery, perceived general health and (1) the occurrence of musculoskeletal complaints in the past 12 months, (2) chronic complaints during at least 3 months, and (3) complaints which led to sickness absence. In logistic regression analysis odds ratios (ORs) were estimated for all relevant risk factors. RESULTS: Self-reported factors of physical load were associated with the occurrence of back pain (OR=1.85), neck pain (OR=1.88), and shoulder pain (OR=1.87) but these factors were not associated with chronic complaints and musculoskeletal sickness absence. Physical load showed a trend with the number of musculoskeletal complaints with ORs of 2.47 and 4.13 for two and three musculoskeletal complaints, respectively. No consistent influence of psychosocial factors on complaints, chronicity, or sickness absence was observed. A perceived moderate general health was also a risk factor, and strongest associations were observed for sickness absence due to back pain (OR=2.03), neck pain (OR=8.31), and shoulder pain (OR=6.84). CONCLUSIONS: The handling of physical loads among nurses seems to put them at risk for the occurrence of musculoskeletal disorders. The development of these complaints into chronic complaints and associated sickness absence is strongly determined by perceived general health and almost not associated with work-related physical and psychosocial risk factors. When the influence of work-related risk factors on musculoskeletal health is being investigated, the general health status of individual workers should be taken into account.     

Psychological evaluation of the emotional effects of a community toxic exposure

OBJECTIVE: We sought to assess the emotional effects of a major community toxic release while controlling the potential effects of response bias associated with litigation. METHODS: Participants included 152 exposed adult litigants and a matched unexposed comparison group (n = 76). Psychological assessment methods included: (1) Minnesota Multiphasic Personality Inventory-2; (2) Symptom Checklist-90-Revised; and (3) Impact of Event Scale-Revised. RESULTS: Ten to 40% of the exposed group demonstrated emotional distress (compared with a 5% comparison baseline) depending on indicator and cutoff score used. CONCLUSIONS: The psychological consequences of a community toxic exposure were present even when exaggeration was carefully controlled. Accounting for exaggeration in the assessment of subjective psychological complaints provides a more accurate view of the subjective emotional state of persons who have experienced toxic exposure thereby facilitating appropriate clinical management of their mental health needs.     

Medication use associated with exposure to manganese in two Ohio towns

This report describes the use of medications as a proxy when medical record reviews are unavailable, to study the health effects of residents environmentally exposed to air-manganese (n = 185) compared to unexposed residents (n = 90). Participants’ current medication lists and medication questionnaire responses were collected in clinical interviews and categorized into 13 domains. Exposed participants reported fewer hours of sleep than controls (6.6 vs. 7.0). The exposed used significantly more medications than unexposed participants (82.2 % vs. 67.8 %) and, when adjusting for age, education, and personal income, also for pain (aOR = 2.40) and hypothyroidism (aOR = 7.03). Exposed participants with higher air-Mn concentrations, monitored for 10 years by the U.S. Environmental Protection Agency, were 1.5 times more likely to take pain medications. The exposed participants take significantly more medications than unexposed participants in the categories of hypothyroidism, pain, supplements, and total medications.     

Measuring the Impact of Hurricane Katrina on Access to a Personal Healthcare Provider: The Use of the National Survey of Children’s Health for an External Comparison Group

This paper examined the effect of Hurricane Katrina on children’s access to personal healthcare providers and evaluated the use of propensity score methods to compare a nationally representative sample of children, as a proxy for an unexposed group, with a smaller exposed sample. 2007 data from the Gulf Coast Child and Family Health (G-CAFH) Study, a longitudinal cohort of households displaced or greatly impacted by Hurricane Katrina, were matched with 2007 National Survey of Children’s Health (NSCH) data using propensity score techniques. Propensity scores were created using poverty level, household educational attainment, and race/ethnicity, with and without the addition of child age and gender. The outcome was defined as having a personal healthcare provider. Additional confounders (household structure, neighborhood safety, health and insurance status) were also examined. All covariates except gender differed significantly between the exposed (G-CAFH) and unexposed (NSCH) samples. Fewer G-CAFH children had a personal healthcare provider (65 %) compared to those from NSCH (90 %). Adjusting for all covariates, the propensity score analysis showed exposed children were 20 % less likely to have a personal healthcare provider compared to unexposed children in the US (OR = 0.80, 95 % CI 0.76, 0.84), whereas the logistic regression analysis estimated a stronger effect (OR = 0.28, 95 % CI 0.21, 0.39). Two years after Hurricane Katrina, children exposed to the storm had significantly lower odds of having a personal health care provider compared to unexposed children. Propensity score matching techniques may be useful for combining separate data samples when no clear unexposed group exists.     

Measuring the impact of Hurricane Katrina on access to a personal healthcare provider: the use of the National Survey of Children's Health for an external comparison group

This paper examined the effect of Hurricane Katrina on children's access to personal healthcare providers and evaluated the use of propensity score methods to compare a nationally representative sample of children, as a proxy for an unexposed group, with a smaller exposed sample. 2007 data from the Gulf Coast Child and Family Health (G-CAFH) Study, a longitudinal cohort of households displaced or greatly impacted by Hurricane Katrina, were matched with 2007 National Survey of Children's Health (NSCH) data using propensity score techniques. Propensity scores were created using poverty level, household educational attainment, and race/ethnicity, with and without the addition of child age and gender. The outcome was defined as having a personal healthcare provider. Additional confounders (household structure, neighborhood safety, health and insurance status) were also examined. All covariates except gender differed significantly between the exposed (G-CAFH) and unexposed (NSCH) samples. Fewer G-CAFH children had a personal healthcare provider (65 %) compared to those from NSCH (90 %). Adjusting for all covariates, the propensity score analysis showed exposed children were 20 % less likely to have a personal healthcare provider compared to unexposed children in the US (OR = 0.80, 95 % CI 0.76, 0.84), whereas the logistic regression analysis estimated a stronger effect (OR = 0.28, 95 % CI 0.21, 0.39). Two years after Hurricane Katrina, children exposed to the storm had significantly lower odds of having a personal health care provider compared to unexposed children. Propensity score matching techniques may be useful for combining separate data samples when no clear unexposed group exists.