A clinical trial of treating asthma of moderate severity with beclomethasone dipropionate aerosol]

In order to investigate the efficacy of steroid inhalation in treating asthma of moderate severity, a single-blind, randomized short-term (3-4 weeks) trial was performed in 25 asthmatics uncontrolled by salbutamol inhalation, oral aminophylline and beta 2-agonist. 22 patients finished the trial. Among them, twelve received beclomethasone dipropionate 300 mcg/day and ten received placebo. There was significant improvement in asthmatic symptoms and pulmonary function (FEV1.0, V50, V25) in the group treated with steroid inhalation at the end of this trial, whereas no significant changes were observed in the placebo group. The results demonstrated that steroid inhalation could effectively control asthma of moderate severity.     

Health-related quality of life in moderate asthma: 400 microg hydrofluoroalkane beclomethasone dipropionate vs 800 microg chlorofluorocarbon beclomethasone dipropionate. The Study Group

OBJECTIVE: To compare the effect of hydrofluoroalkane-134a (HFA) beclomethasone dipropionate (BDP; 400 microg/d) with that of chlorofluorocarbon (CFC) BDP (800 microg/d) on asthma health-related quality of life in a 12-week, parallel-group, multicenter study. BACKGROUND: HFA-BDP is a new CFC-free preparation of BDP, which was developed as a result of CFCs being phased out from metered dose inhalers. METHODS: Following 7 to 12 days of prednisone, 30 mg/d, 347 adults with moderate asthma were randomized to receive either 400 microg/d HFA-BDP, 800 microg/d CFC-BDP, or HFA placebo for 12 weeks (all other oral and inhaled steroids were withdrawn). Patients completed the Asthma Quality of Life Questionnaire (AQLQ), and clinical asthma status was measured at the end of a run-in period, at randomization (after oral steroid treatment), and at the end of the study treatment. RESULTS: Sixty-one patients withdrew, 43 due to worsening asthma (33 placebo; 5 HFA-BDP; 5 CFC-BDP). There was a deterioration in the AQLQ score (- 0.81) in the placebo group, and the difference between this and the stability observed in both the HFA-BDP group (+ 0.13) and the CFC-BDP group (- 0.03) was statistically significant (p 相似文献   

Treatment of exercise-induced asthma with beclomethasone dipropionate in children with asthma.

A new hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP) aerosol markedly increases drug delivery to the airways. Therefore, even low doses of HFA-BDP should be effective, and the present study assesses this. A randomised, double-blind, crossover study was used to compare the effect of placebo, HFA-BDP 50 microg or 100 microg given q.d. (QVAR(TM) Autohaler(TM); 3M Pharmaceuticals, St. Paul, MN, USA) on exercise-induced bronchoconstriction and exhaled nitric oxide (eNO). After a 14-day run-in, 25 children (5-14 yrs old) entered three 4-week treatment periods, separated by a 1-week washout. After each period, the fall in forced expiratory volume in one second (FEV1), after an exercise test, and eNO were measured. Significant treatment effects with no carry-over or period effects were seen for both eNO and maximum fall in FEV1 after exercise. Differences were seen between placebo (fall in FEV1=27.9%; eNO=14.4 parts per billion (ppb)) and either dose of HFA-BDP, but not between the two active doses (50 microg: fall in FEV1=20.8%, eNO=9.3 ppb; 100 microg: fall in FEV1=20.9%, eNO=8.9 ppb). In conclusion, low q.d. doses of hydrofluoroalkane-beclomethasone dipropionate reduced exhaled nitric oxide and exercise-induced bronchoconstriction. Further studies are needed to assess whether q.d. administration of beclomethasone dipropionate is as effective as b.i.d. administration.     

Treatment of steroid-dependent asthma patients with beclomethasone dipropionate aerosol.

Fifty-two steroid-dependent adults with chronic perennial asthma were transferred to beclomethasone dipropionate aerosol. The tests demonstrated a significant improvement with beclomethasone in terms of the diary score, bronchodilator use, and PEF and FEV1.0 measurements, as compared with the previous period of prednisolone treatment. Before the transfer, 26 of the patients displayed one or more diseases or symptoms which were probably due to systemic steroid medication. Morning cortisol levels, along with the response to tetracosactrin had in all cases returned to normal when tests were carried out 41 days after transfer to beclomethasone dipropionate. In a group of 12 patients with the lowest 11-OHCS basal values, the mean of their 11-OHCS values during prednisolone treatment was as low as 0.14 plus or minus 0.06 mumol/l, but tetracosactrin challenge induced an elevation to a normal level, 0.33 plus or minus 0.13 mumol/l. After 41 days of beclomethasone treatment, the corresponding values were 0.56 plus or minus 0.90 plus or minus 0.28 mumol/l. Thirty-seven patients experienced one or more disturbing symptoms after transfer to beclomethasone. In many cases, the symptoms of allergic rhinitis were troublesome and persistent leading to a sixfold increase in the use of antihistaminic tablets. When the patients had learned to exhale through the nose following beclomethasone inhalation, the use of antihistaminic tablets again diminished to some extent. Moreover, two cases of ulcerative colitis were encountered during the beclomethasone treatment. During a follow-up period of one year, 14 patients were again receiving prednisolone; most often, this was due to worsening of the asthma because of respiratory infections. During the beclomethasone treatment, a continuous significant improvement in PEF was noted after isoprenaline inhalation, suggesting that further benefit may be obtained by the employment of bronchodilator aerosols as an essential part of the treatment.     

Comparison of budesonide and beclomethasone dipropionate in patients with severe chronic asthma: assessment of relative prednisolone-sparing effects

The relative prednisolone-sparing effects of inhaled budesonide 400 micrograms daily and beclomethasone dipropionate (BDP) 400 micrograms daily were compared in a double-blind crossover study of 26 patients with chronic asthma requiring treatment with BDP and oral prednisolone in a daily dose of 5 mg or greater. During each period of the trial budesonide and BDP were inhaled via conventional pressurized inhalers in a dose of 100 micrograms four times daily. Prednisolone was reduced by 1 mg per month from the patient's normal maintenance dose to zero or to the point at which asthmatic symptoms became unacceptable. The mean reduction in prednisolone dose during BDP treatment was 2.65 mg compared with 1.8 mg at the end of the budesonide period. The difference between the prednisolone-sparing properties of BDP and budesonide assessed in this way in this group of patients was statistically significant in favour of BDP. The mean minimum prednisolone doses at the end of the treatment periods were 3.46 mg for BDP and 4.3 mg for budesonide. Since inhaled steroids were not withdrawn the absolute prednisolone-sparing properties of the two drugs were not assessed, and thus a pharmacological potency ratio cannot be derived from the results. It is concluded that BDP is marginally more potent than budesonide in its prednisolone-sparing properties.     

A comparison of clinical use of fluticasone propionate and beclomethasone dipropionate in pediatric asthma

Inhaled steroids play a very important role in the prevention and treatment of asthma. Previous studies indicated that fluticasone propionate (FP) had low bioavailability and high local potency. However, the laboratory data in these studies were not obtained among Taiwan population. It is very important that native data should be established. Thus a 12-week research program was designed, involving 77 patients, 51 for FP group and 26 for beclomethasone dipropionate (BD) group. The objects were victims of moderate to severe asthma and their age ranged from 4 to 14 years old. An open, comparative and randomized method was adopted. Except for the 4-week-later daytime symptom score(P = 0.033, BD group was better), no other significant differences were found between the two groups in the symptom score improvement(P > 0.05). All the P-values for the daytime & night-time scores were lower than 0.001, which means obvious improvement after treatment in both groups. P-value for PEF improvement was 0.003 after 4 weeks (BD group was better) and 0.943 after 8 weeks; for FEV1 improvement, it was 0.005 after 4 weeks(BD group was better) and 0.252 after 8 weeks; and for FEV1/FVC improvements, it was 0.067 after 4 weeks and 0.097 after 8 weeks. There was no statistic significance in total eosinophil count (TEC), IgE, eosinophil cationic protein (ECP) serum level changes after 4 or 8 weeks. Adverse effects were all anticipated and no statistic significance showed up, either, between the two groups or in the cortisol levels (P > 0.05). In conclusion, native data indicated that the potency of 100 micrograms of FP was equal to that of 200 micrograms of BD and that few side effects were noted in FP group. It is recommended that this drug be introduced for clinical use.     

A fixed combination of fluticasone and salmeterol permits better control of asthma than a beclomethasone dipropionate and montelukast combination

It is now recommended to add an inhaled long-acting beta 2-agonist, or as an alternative, to add a leukotriene-antagonist, in patients whose asthma is insufficiently controlled with an inhaled corticosteroid alone. A randomised, multicentre, open-label, parallel-group study was carried out in 246 patients of at least 15 years, whose asthma was not adequately controlled with a medium dose of an inhaled corticosteroid. They received either fluticasone/salmeterol combination 250/50 micrograms one inhalation twice daily or CFC beclomethasone dipropionate 250 micrograms two puffs twice daily plus montelukast 10 mg in the evening for 12 weeks. The mean morning PEFR (main criterion) was significantly (p = 0.017) more improved with fluticasone/salmeterol (+44.2 L/min) than with beclomethasone dipropionate plus montelukast (+31.0 L/min). Other outcomes showed significantly better improvements (p 0.022 Pound) with fluticasone/salmeterol than with beclomethasone plus montelukast. The two treatments were well tolerated. Fluticasone/salmeterol provided a better asthma control than beclomethasone dipropionate plus montelukast in patients insufficiently controlled with an inhaled corticosteroid alone.     

Twice-daily beclomethasone dipropionate in the treatment of childhood asthma

Chronic nonsteroid-dependent childhood asthma was treated by adding beclomethasone dipropionate (BDP) or placebo (P) to the daily regimen of theophylline (T). Subjects (6-12 years) were selected based on daily control of asthma by T at necessary T levels in sera of 10-20 micrograms. Active BDP (200 micrograms b.i.d.) and P groups were randomly assigned. Each subject's baseline values were evaluated on a 4-week open phase followed by a 10-12 week double-blind phase. Daily diaries were kept for signs, symptoms, Wright peak flow recordings, and medication requirements. Visits were monitored for urine and serum cortisols, pulmonary function tests (PFT), objective changes, and medication compliance. Demographics between both groups were nonsignificant (NS). Baseline PFTs in P group were significantly better than the BDP group. Serum and urine cortisols and ACTH responses were NS (p less than 0.05). Drug efficacy for asthma characteristics was significantly improved in the BDP group (p less than 0.05) only. The BDP group maximized their response by 8 weeks, with improvement of their FEV1 and FEF25-75 PFT. Thus, b.i.d. BDP provided good asthma control and the twice-daily program should insure improved compliance.     

Hydrofluoroalkane-134a beclomethasone dipropionate, 400 microg, is as effective as chlorofluorocarbon beclomethasone dipropionate, 800 microg, for the treatment of moderate asthma

OBJECTIVE: The improved lung deposition of hydrofluoroalkane-134a beclomethasone dipropionate (HFA-BDP) extrafine aerosol compared with chlorofluorocarbon beclomethasone dipropionate (CFC-BDP) suggests that lower doses of HFA-BDP may be required to provide equivalent asthma control. The present study was undertaken to test this hypothesis. DESIGN: A 10- to 12-day run-in period confirmed that patients met established criteria of at least moderate asthma and the asthma was inadequately controlled by current therapy (inhaled beta-agonist and CFC-BDP [< or = 400 microg/d]). A short course of oral prednisone, 30 mg/d for 7 to 12 days, was followed to establish the patients were steroid responsive and to provide an "in-study" baseline of "optimal" asthma control. PATIENTS: A total of 347 patients were then randomized to HFA-BDP 400 microg/d, CFC-BDP 800 microg/d, or HFA-placebo for 12 weeks. RESULTS: Morning peak expiratory flow (AM PEF) measurements showed that HFA-BDP 400 microg/d achieved equivalent control of asthma to CFC-BDP 800 microg/d at all time intervals after oral steroid treatment. All other efficacy variables supported the AM PEF results and both active treatments were more effective than placebo. The safety profile of HFA-BDP compared favorably with that of CFC-BDP with no unexpected adverse events reported. CONCLUSIONS: These findings demonstrate that HFA-BDP provides equivalent control of moderate or moderately severe asthma as CFC-BDP in the population studied, but at half the total daily dose.     

Steroid-dependent asthma treated with inhaled beclomethasone dipropionate. A long-term study.

The efficacy of inhaled beclomethasone dipropionate has been examined in 44 steroid-dependent asthmatics observed for 9 months to 2 years. A 3-month double-blind trial found that subjects treated with beclomethasone had a significant diminution in symptoms, were able to reduce their use of medication, and had improved maximum expiratory flow rates. Approximately one half were able to discontinue the use of oral prednisone within 9 months after starting beclomethasone, and a further one third reduced their dose by at least 50%. No characteristics could be defined to predict responsiveness to beclomethasone. The effectiveness of beclomethasone was sustained for as long as 2 years and was not associated with any abnormal urine, blood, or serum values or chest X-ray findings. Candidiasis of the palate appeared in approximately one third of the subjects and was usually transient. The chronic use of beclomethasone did not result in endocrine suppression.     

A comparison of inhaled budesonide and beclomethasone dipropionate in childhood asthma

The objective of this study was to compare the clinical effects of beclomethasone dipropionate (BDP) and budesonide in asthmatic children using two common ways of administration. Twenty-one children, aged 4-14 years, who regularly used inhaled corticosteroids for their control of asthma were included in the study. The drugs were studied by using a double-blind randomized cross-over design trial with a single-blind placebo period at the end. Each period lasted 3 weeks. The dosage was 100 micrograms b.i.d. for both drugs. Budesonide was administered via a spacer inhaler (Inhalet), and beclomethasone dipropionate via a standard actuator. Compared with placebo, both drugs significantly improved PEFR values for morning (20% for budesonide and 14% for BDP) and evening (14% for budesonide and 9% for BDP). Both morning and/or evening peak flows were significantly higher during the budesonide treatment as compared with the BDP treatment. In comparison with the placebo period, FEV1.0 was significantly improved with budesonide but not with BDP. Plasma cortisol, WBC counts, differential and eosinophilia counts in blood were determined at the beginning and the end of each period. All of the values except for the eosinophil counts were within normal ranges. Candida was looked for but not found in any case. No other adverse effects were registered. For most of the children, a deterioration of the state of their asthma and increased need for concomitant therapy during the placebo period confirmed their steroid dependence. The number of administrations with concomitant anti-asthmatic therapy increased during placebo by 61% as compared with the budesonide therapy, and by 40% compared with the BDP therapy.     

Dose-related effect of beclomethasone dipropionate on airway responsiveness in asthma

The effects of twice daily inhaled beclomethasone dipropionate (BDP) at two dose levels (500 and 1,000 micrograms daily) on the airway responsiveness to inhaled histamine was evaluated by a randomized, single-blind, cross-over study in 10 patients with stable asthma. The 12-week study began with a 3-week run-in period of baseline treatment, which was continued unchanged throughout the study, and the two treatment periods were separated by a 3-week placebo period. Patients attended the laboratory every 3 weeks for spirometry and histamine inhalation tests to determine the provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 s (PC20 of FEV1). There was a similar significant improvement (p less than 0.05) in mean FEV1 after both treatments. There was no significant change in PC20 after treatment with 500 micrograms daily, the geometric mean being 0.587 mg/ml after the placebo period and 0.860 mg/ml after BDP treatment. There was a significant improvement in PC20 (1.930 mg/ml) after treatment with 1,000 micrograms BDP daily in comparison with the placebo and treatment periods with 500 micrograms BDP daily (p less than 0.001). These results suggest that higher doses than usual of inhaled BDP must be used to control airway responsiveness in asthmatics.     

Inhaled beclomethasone dipropionate improves acoustic measures of voice in patients with asthma.

BACKGROUND: Inhaled corticosteroids have the potential to produce upper-airway side effects such as hoarseness. As new compounds and delivery devices are developed and compared, it is difficult to quantify their adverse upper-airway effects. OBJECTIVE: We undertook the following study to test the ability of an acoustic analysis technique to quantify changes in vocal function in steroid-naive patients with asthma who receive inhaled beclomethasone dipropionate (BDP), 1,000 microg/d for 4 months. METHODS: Patients self-administered one of four regimens of inhaled BDP. Group 1 patients received one 250-microg puff qid via metered-dose inhaler (MDI); group 2 patients received one 250-microg puff qid via MDI with a holding chamber; group 3 patients received two 250-microg puffs bid via MDI; and group 4 patients received two 250-microg puffs bid via MDI with a holding chamber. A smaller cohort of nonsmoking asthmatic patients was managed without steroid intervention for 4 months. At baseline and again at 8 weeks and 16 weeks after the initiation of BDP treatment, patients underwent spirometry and methacholine challenge. At baseline and again at 2, 4, 8, 12, and 16 weeks, patients underwent voice recording for analysis of voice parameters. The recorded vowels were low-pass filtered (10 KHz), digitized (22 KHz), and analyzed by software to obtain two acoustic measures: (1) jitter, the cycle-to-cycle variation in the time period of the voice signal; and (2) shimmer, the cycle-to-cycle variation in voice signal amplitude. RESULTS: We recruited 77 patients for randomization to inhaled steroid therapy and 10 patients who continued to receive only occasional inhaled bronchodilator therapy. In all active treatment groups, FEV(1), FVC, and provocative concentration of methacholine causing a 20% fall in FEV(1) improved significantly after BDP treatment. Mean jitter scores, a measurement of variation in voice pitch, were not significantly influenced by BDP treatment. However, mean shimmer scores, a reflection of perturbation in vocal amplitude, fell significantly (p < 0.05) in the active treatment groups. These reductions in shimmer scores were not significantly different in the active treatment groups. Shimmer scores in the bronchodilator-treated group were unchanged during the 16 weeks of follow-up. CONCLUSIONS: Our data show that a simple and noninvasive acoustic analysis of voice is sensitive to subclinical changes associated with inhaled corticosteroid therapy. We have shown that 1,000 microg/d of inhaled BDP actually improves specific acoustic measures of voice in patients with inadequately controlled asthma. These improvements were uninfluenced by dosing schedule and whether a spacing chamber was used.     

Efficacy and safety of inhaled ciclesonide compared with chlorofluorocarbon beclomethasone dipropionate in adults with moderate to severe persistent asthma

BACKGROUND AND OBJECTIVE: Inhaled corticosteroids are recognized as first-line therapy in the management of asthma; however, their use may be limited by systemic and local side-effects. Ciclesonide, a novel pro-drug inhaled corticosteroid, is activated in the lungs and is expected to have less systemic and local side-effects. This study evaluated the efficacy and safety of ciclesonide in hydrofluoroalkane (HFA) compared with beclomethasone dipropionate (BDP) in a chlorofluorocarbon (CFC) formulation in adult patients with moderate to severe asthma. METHODS: This was a multicentre, randomized, open-label, parallel-group comparative study. The patients were given 800 microg/day of CFC-BDP in the four-week baseline period. After the baseline period, 319 patients were randomly allocated into three groups which, respectively, received HFA-ciclesonide 400 microg/day (without a spacer), HFA-ciclesonide 800 microg/day (without spacer) and CFC-BDP 800 microg/day (with spacer) for the eight-week treatment period. The primary efficacy variable was morning PEF. RESULTS: The morning PEF increased by 16.02 L/min in the 400 microg HFA-ciclesonide group, 23.98 L/min in the 800 microg HFA-ciclesonide group and 5.91 L/min in the 800 microg CFC-BDP group. Better outcomes were achieved by the use of 800 microg/day of HFA-ciclesonide compared with 800 microg/day of CFC-BDP (P = 0.001). There was no difference in adverse events between the groups. CONCLUSION: In adult patients with moderate to severe asthma, 800 microg/day of HFA-ciclesonide was significantly more effective than 800 microg/day of CFC-BDP. Ciclesonide at doses of 400 microg/day and 800 microg/day was safe and well tolerated.     

Adherence rate to beclomethasone dipropionate and the level of asthma control

There are only a few studies assessing the relationship between adherence rate to ICS, as assessed by electronic monitoring, and the level of asthma control in childhood. The present study was carried out to examine the relationship between adherence to beclomethasone diproprionate (BDP) as well as other factors related to poor asthma control. In this prospective cohort study, 102 steroid na?ve randomly selected subjects with persistent asthma, aged 5-14 years were prescribed 500-750?μg daily of BDP-CFC and followed during one year. Adherence to BDP was measured electronically in the 4th, 8th and 12th months of study. The level of asthma control was classified as either controlled or uncontrolled instead of the current three categories recommended by the Global Initiative for Asthma (GINA). Mean adherence rate was higher in patients with controlled asthma during follow-up, but went down from 60.4% in the 4th month to 49.8% in the 12th month (p?=?0.038). Conversely, among patients with uncontrolled asthma, the mean adherence rate decreased from 43.8% to 31.2% (p?=?0.001). Multivariate analysis showed that the level of asthma control was independently associated to the adherence rate in all follow-up visits (p-values equal or lower than 0.005). The level of asthma control was directly proportional to adherence rate. Our results suggest that a BDP daily dose by 300?μg seems to be enough to attain control over mild and moderate persistent asthma, including exercise induced asthma.     

Comparison of the effects of sequential or simultaneous administration of salbutamol and beclomethasone dipropionate

The effect of the simultaneous administration of salbutamol and beclomethasone dipropionate, from a combination inhaler, was compared with the same doses given with an interval of 10 min, from separate inhalers, in a group of 40 asthmatic females. The double-blind parallel-group study was well balanced and lasted 4 weeks. Both groups showed a similar improvement in thrice-weekly lung function values and daily symptoms in week 4 compared to week 1. There were no other differences and no adverse reactions. The combination inhaler is a useful alternative for maintenance treatment in patients who require an inhaled steroid.     

Inhaled beclomethasone dipropionate reverts tolerance to the protective effect of salmeterol on allergen challenge

STUDY OBJECTIVE: One week of regular treatment with salmeterol can induce tolerance to the protective effect of a beta2-agonist on early airway response to allergen (EAR). The objective was to assess whether inhaled corticosteroids revert tolerance to salmeterol. STUDY DESIGN: The study had a randomized, double-blind, placebo-controlled design. PATIENTS AND METHODS: Twelve subjects with mild allergic asthma and positive result of specific bronchial provocation test (sBPT) to allergen underwent three sBPTs, separated by 1 week. sBPT was done in all subjects after a single dose (T1) and after 1 week of regular treatment with inhaled salmeterol (50 microg bid) (T2) in order to induce tolerance. Subjects were then randomized to receive either the same dose of salmeterol + beclomethasone dipropionate (BDP, 500 microg bid) (group 1, n = 6) or placebo + BDP (group 2, n = 6) for 1 week before sBPT (T3). RESULTS: After a single dose of salmeterol (T1), all subjects were protected against EAR, whereas after 1 week of regular treatment, the protective effect of salmeterol was totally or partially lost (T2). Maximum FEV1 percent fall (MaxdeltaFEV1%) after allergen inhalation was significantly higher at T2 than at T1. All subjects except one of group 1 were protected against EAR after salmeterol + BDP (T3), and MaxdeltaFEV1% at T3 (median, 12%; range, 4 to 6%) was significantly lower than T2 (median, 22%; range, 12 to 43%; p < 0.05 by Wilcoxon test). Subjects of group 2 did not show any significant protection against EAR after placebo + BDP treatment (T3) MaxdeltaFEV1% at T2 (median, 31%; range, 9 to 40%) and T3 (median, 31%; range, 3 to 42%; not significant). CONCLUSIONS: In conclusion, the addition of inhaled BDP partially restored the bronchoprotective effect of salmeterol on allergen challenge that was lost after 1 week of regular treatment with salmeterol alone. This ability of BDP in reverting tolerance cannot be ascribed to a direct effect of corticosteroids per se on allergen challenge in this group of asthmatics.     

A placebo-controlled blinded comparison of nedocromil sodium and beclomethasone dipropionate in bronchial asthma

Two hundred and two patients aged 12–78 with chiefly moderate to severe asthma took part in a multicenter randomized blined group comparison of nedocromil sodium (NS) 4 mg four times daily, beclomethasone dipropionate (BD) 0.1 mg four times daily, and placebo. Patients were assessed at the start and end of a two week baseline and after three and six weeks of treatment. Compared with placebo, both NS and BD significantly improved day-time dyspnoea and day and nighttime cough, as assessed by diary card scores. Lung function (FEV₁) was significantly improved in the BD group. In the NS group there was also a significant reduction in concomitant use of inhaledβ ₂-agonists. Overall opinions of efficacy by clinicians and patients were significantly in favor of both active treatments over placebo. There were no significant differences between the three treatments for peak expiratory flow rates, morning tightness or nighttime dyspnoea. Comparison between the two active treatments showed no significant differences in any of the variables.