Olli Impivaara

Determinants of sciatica and low-back pain

Several factors were studied for their association with the prevalence of chronic low-back syndromes, sciatica, and unspecified low-back pain (LBP) in 2,946 women and 2,727 men (age range, 30-64 years) participating in the Mini-Finland Health Survey, a project aimed at comprehensive evaluation of the populations health. On the basis of a standardized clinical examination, a physician diagnosed sciatica in 5.1% and LBP in 11.6% of the subjects. Those with a previous traumatic back injury had a 2.5-fold risk of having sciatica or LBP. The fractions of sciatica and LBP attributable to such back injuries were estimated to be 16.5% and 13.7%, respectively. Sum indices of both physical and mental stress at work were found to be directly proportional to the prevalence of sciatica and LBP. Smokers had an increased risk of LBP, and body height was related positively to the prevalence of sciatica. These associations, however, were inconsistent between sex and age subgroups. In the presence of osteoarthritis in the knee, hip, or hand, LBP was prevalent (adjusted odds ratio [OR], 5.3; 95% confidence interval [CI], 4.1-6.9), but sciatica was not (OR, 1.1; 95% CI, 0.7-1.7). Diabetics were found to have a significantly decreased prevalence of LBP (OR, 0.4; 95% CI, 0.3-0.8). Many factors, independent of each other, determine the occurrence of chronic low-back syndromes. The determinants of sciatica and LBP are different to some extent.

Depression and cardiovascular diseases

We first review the asSociations between depression and cardiovascular diseases (CVDs). Then we examine them in the nationally representative Mini‐Finland Health Survey, which covers 8,000 persons. Chronic somatic diseases and mental disorders were diagnosed using standardized methods. Cross‐sectionally, CVDs and neurotic depression were asSociated both before and after adjustment for covariates. The strongest asSociations were observed in the case of severe CVDs. During a 6.6 year follow‐up, the risk of CVD death and coronary death was elevated in depressed persons both with and without CVDs at entry. Much of the cross‐sectional asSociation is probably due to depression caused by CVDs. The outcome of CVD may be poorer in depressed persons. The hypothesis that depression is a cause of CVDs requires further study.

Vitamin D Status and the Risk of Cardiovascular Disease Death

Accumulating evidence suggests that inadequate vitamin D levels may predispose people to chronic diseases. The authors aimed to investigate whether serum 25-hydroxyvitamin D (25(OH)D) level predicts mortality from cardiovascular disease (CVD). The study was based on the Mini-Finland Health Survey and included 6,219 men and women aged > or =30 years who were free from CVD at baseline (1978-1980). During follow-up through 2006, 640 coronary disease deaths and 293 cerebrovascular disease deaths were identified. Levels of 25(OH)D were determined from serum collected at baseline. Coxs proportional hazards model was used to assess the association between 25(OH)D and risk of CVD death. After adjustment for potential confounders, the hazard ratio for total CVD death was 0.76 (95% confidence interval (95% CI): 0.60, 0.95) for the highest quintile of 25(OH)D level versus the lowest. The association was evident for cerebrovascular death (hazard ratio = 0.48, 95% CI: 0.31, 0.75) but not coronary death (hazard ratio = 0.91, 95% CI: 0.70, 1.18). A low vitamin D level may be associated with higher risk of a fatal CVD event, particularly cerebrovascular death. These findings need to be replicated in other populations. To demonstrate a causal link between vitamin D and CVD, randomized controlled trials are required.

Reliability and validity of interview data on chronic diseases The mini-Finland health survey

The Mini-Finland Health Survey was designed to obtain a comprehensive picture of health and of the need for care in Finnish adults, and to develop methods for monitoring health in the population as a whole. Out of a nationally representative sample of 8000 people aged 30 or over, 7217 (90%) were both interviewed at home by local public health nurses using simple open-ended questions and, independently of this interview, subsequently examined in a two-phase health examination. The estimate of chronic morbidity based on the health interview (56%) was close to the prevalence of definite somatic diseases diagnosed in the health examination (54%), and the agreement between the two methods was moderate (kappa = 0.53). The estimated prevalence of cardiovascular diseases was the same (23%) in the health interview and in the health examination; the agreement was substantial (kappa = 0.74). The prevalence of respiratory and musculoskeletal diseases and mental disorders was underestimated in the interview by 52, 25 and 78%, respectively; the agreement between results of the two methods was relatively low (kappa = 0.43, 0.38 and 0.30, respectively). These results suggest that both the health examination and the health interview methods, as used in this survey, have useful applications in monitoring the populations health.

Osteoarthritis in the carpometacarpal joint of the thumb. Prevalence and associations with disability and mortality.

BACKGROUND This study was designed to investigate the prevalence of osteoarthritis in the carpometacarpal joint of the thumb in adults thirty years of age or older in Finland. METHODS Between 1978 and 1980, a representative population sample of 8000 Finns thirty years of age or older were invited to have a comprehensive health examination; 90% accepted. Hand radiographs were made of 3595 subjects. Since the examination, the subjects have been followed systematically to assess work disability and mortality by reviewing registers covering the whole population. RESULTS The age-adjusted prevalence of thumb carpometacarpal osteoarthritis of Kellgren grade 2, 3, or 4 was 7% for men and 15% for women. After adjustment for age, sex, and other alleged risk factors, body mass index was found to be directly proportional to the prevalence of thumb carpometacarpal osteoarthritis in both sexes. The adjusted odds ratio was 1.29 (95% confidence interval, 1.15 to 1.43) per 5-kg/m(2) increment in body mass index. No significant association was found between the physical workload history and thumb carpometacarpal osteoarthritis. Restricted mobility of the thumb and local tenderness and swelling were frequently found in conjunction with radiographic evidence of thumb carpometacarpal osteoarthritis. Advanced (grade-3 or 4) thumb carpometacarpal osteoarthritis predicted the total mortality rate in men (adjusted relative risk, 1.32; 95% confidence interval, 1.03 to 1.69). Radiographic signs of thumb carpometacarpal osteoarthritis did not predict work disability. CONCLUSIONS and CLINICAL RELEVANCE Obesity is a strong determinant of thumb carpometacarpal osteoarthritis in both sexes. The effect of thumb carpometacarpal osteoarthritis on disability and mortality in the general population is modest. Because of the rarity of ensuing disability, carpometacarpal osteoarthritis of the thumb is likely to be underdiagnosed in clinical practice.

Risk factors for subarachnoid hemorrhage in a longitudinal population study

The known risk factors of atherosclerotic diseases may be involved in the development of a subarachnoid hemorrhage. We studied the morbidity and mortality due to subarachnoid hemorrhage among 42,862 men and women aged 20-69 years who had participated in a large health survey in Finland. During a mean follow-up of 12 years, 102 non-fatal and 85 fatal cases of subarachnoid hemorrhage were observed. The total incidence was 37 per 100,000 person-years. Smoking and hypertension were positively associated and body mass index was inversely associated with the risk of subarachnoid hemorrhage. These associations were not confounded by age or each other. No statistically significant association with risk was detected for serum cholesterol level, hematocrit content, known heart disease, or diabetes. The risk was especially elevated among lean hypertensive subjects and lean smoking subjects. The age-adjusted relative risks of subarachnoid hemorrhage for lean, hypertensive smokers were 18.3 (95% confidence interval (CI), 7.8-42.7) among women and 6.7 (95% CI, 2.3-19.7) among men as compared to the risk among subjects without these risk factors. We conclude that modifiable risk factors are predictive of subarachnoid hemorrhage, for which reason subarachnoid hemorrhage may in part be preventable. Leanness combined with arterial hypertension and/or smoking, in particular, poses a substantially elevated risk.

Association of overweight, trauma and workload with coxarthrosis: A health survey of 7,217 persons

In a population sample health survey, body mass, previous trauma and physical stress were studied for associations with coxarthrosis. A sample of 8,000 persons representative of the Finnish population aged 30 or over was invited for examination, and 90 percent participated. On the basis of a standardized clinical examination, a physician diagnosed coxarthrosis in 6 percent of the women and 4 percent of the men. The prevalence rose with age. In persons with a past traumatic lower-limb injury, the odds ratio of unilateral coxarthrosis was 2.1 and of bilateral coxarthrosis 1.5, as adjusted for sex, age and other determinants using logistic regression. The sum index reflecting self-reported features of physical stress in present or previous occupations was directly proportional to the prevalence of coxarthrosis. Body mass index (kg/m2) was closely associated with bilateral coxarthrosis; the adjusted odds ratio (95 percent confidence intervals) for indices > 35, compared to those < 25, was 2.8 (1.4-5.7). In terms of the population attributable fraction, prior trauma, physical stress and body mass were estimated to explain 59 percent of the prevalence of coxarthrosis. The potential for primary prevention may be great, but longitudinal population studies are necessary to elucidate causal significance of the risk factors.

Bone mineral density in asthmatic women on high-dose inhaled beclomethasone dipropionate

Inhaled corticosteroids are the cornerstone of the modern therapy for asthma. In recent years, inhaled corticosteroids have been used in higher doses than previously. This has caused concern about possible osteoporotic side-effects. We studied bone mineral densities (BMDs) in 19 non-smoking women (mean age 53 years, range 40-63) with newly diagnosed bronchial asthma and 19 voluntary healthy non-smoking women (mean age 53 years, range 43-67). In both groups, 13 subjects were postmenopausal. Patients started beclomethasone dipropionate from the spacer 500 micrograms twice daily as the sole corticosteroid therapy. BMDs were measured with dual-energy x-ray absorptiometry (DEXA) at the lumbar spine (L2-4) and at the left proximal femur (the neck, Wards triangle and the trochanteric region). The measurements were made at baseline and 6 and 12 months thereafter. No significant changes were observed in the measured BMDs in either study group. The results show that inhaled beclomethasone dipropionate therapy 1000 micrograms/day for one year does not affect BMD. Further studies are needed to assess the effects of inhaled corticosteroid on BMD during a longer treatment period.

Risk factors for the development of hip osteoarthritis: a population-based prospective study

OBJECTIVES Potential risk factors and their roles in the aetiology of hip OA are poorly understood. We analysed several alleged risk factors predisposing to hip OA in a 22-yr prospective study. METHODS A comprehensive health survey was carried out in 1978-80 in a nationally representative sample of adult Finns. In 2000-01, 1286 participants in that survey were invited for re-examination, and 909 agreed to participate. After excluding those with hip OA at the baseline and those who were no longer working, a total of 840 subjects constituted the present study population. Hip OA was diagnosed on the basis of a standardized clinical examination by physicians who applied uniform criteria both at the baseline and at the re-examination phase. RESULTS After 22 yrs of follow-up, hip OA was diagnosed in 41 subjects (4.9%). Heavy manual labour predicted the risk of developing hip OA [adjusted odds ratio (OR) 6.7; 95% CI 2.3, 19.5]. Permanent damage as a consequence of any musculoskeletal injury was also an independent predictor of hip OA (adjusted OR 5.0; 95% CI 1.9, 13.3). BMI, smoking, alcohol intake and leisure time physical activity were not factors which were predictive for hip OA. CONCLUSION Heavy physical stress at work and major musculoskeletal injuries are associated with an increased risk of developing clinically diagnosed hip OA.

Clodronate Is Effective in Preventing Corticosteroid-Induced Bone Loss Among Asthmatic Patients

Clodronate is a novel drug used for inhibiting osteoclastic activity. The aim of the present double-blind study was to evaluate the efficacy and tolerability of clodronate (Leiras, Finland) in corticosteroid-induced bone loss among asthmatic patients. Seventy-four adult patients (41 women and 33 men, mean age 57.3 years) having a long history (mean 8.1 years) of oral and inhaled corticosteroid therapy were randomized to four parallel treatment groups: clodronate 800, 1600, or 2400 mg/day, or an identical placebo. The bone mineral density (BMD) of the lumbar spine (L2-4), femoral neck, and trochanter were assessed using dual-energy X-ray absortiometry at entry, 6 months, and 12 months. The baseline BMDs did not differ significantly between the study groups. In the lumbar spine, the mean BMD increased significantly between the baseline and 12-month visit in the clodronate groups of 1600 and 2400 mg/day, 2.6% (0.02 g/cm2, p < 0.02) and 3.0% (0.03 g/cm2, p < 0.01), respectively, but not in the placebo and clodronate 800 mg/day groups. The test for a linear trend (BMD percent change for L2-4) at 12 months was significant (p < 0.02), indicating a dose response to clodronate. The mean BMD values of the femoral neck increased significantly in the 2400 mg/day group, 4.3% (0.03 g/cm2, p < 0.0001), as well as in the trochanter region 2.8% (0.02 g/cm2, p < 0.02). Gastric irritation was the most common adverse effect noted on a clodronate dose of 2400 mg/day. We conclude that oral clodronate is effective in preventing bone loss or increasing bone mass in asthmatic patients having a long history of continuous peroral and inhaled corticosteroid administration.