A register-based cohort study was performed to investigate if men and women in certain occupations with high physical workload had increased risks of developing severe symptomatic osteoarthrosis of the hip and knee, resulting in hospital care. The study population consisted of 250,217 people from the 1980 census, in blue-collar occupations, who had reported the same occupation in the 1960 and 1970 censuses. The study population was followed for hospital care for osteoarthrosis of the hip and knee during 1981-1983 by linkage to the Swedish Hospital Discharge Register. Different blue-collar occupations were classified as high or low with regard to exposure to forces acting on the hip and knee and the frequencies of the outcomes were compared. Male farmers, construction workers, firefighters and some food processing workers had an excess risk of hospitalization due to osteoarthrosis of the hip. Male farmers, construction workers and firefighters also had increased risks of osteoarthrosis of the knee. Female mail carriers had an excess risk of osteoarthrosis of the hip, and female cleaners, of osteoarthrosis of the knee. The findings support the hypothesis that heavy physical work load contributes to osteoarthrosis of the hip and knee.

Accumulating evidence indicates that body weight, alcohol and smoking are associated with psoriasis. However, these factors have scarcely been investigated in relation to onset and disease activity at onset of psoriasis. A population-based case-control study was performed including 373 cases with onset of first-time plaque psoriasis within 12 months and matched healthy controls. Psoriasis activity was measured using the Psoriasis Area and Severity Index (PASI). Analyses were performed using conditional logistic regression. In multivariable analyses for each unit increment in body mass index, there was statistically significant 9% increased risk for psoriasis onset and 7% higher risk for increased PASI. Obesity (body mass index > or =30) compared with normal body weight was associated with a two-fold increased risk for psoriasis onset. Smoking was associated with a 70% increased risk for onset, but was not related to PASI. A positive association with alcohol drinking was observed among men, but not among women. No associations were observed for weight gain and use of smokeless tobacco. Our results indicate that excessive body weight and smoking are risk factors for onset of psoriasis and that higher body mass index increases the PASI of plaque psoriasis at onset.

Good agreement was found between self-reported and register information on sickness absence. Self-reported data on sickness absence may be useful in common epidemiological applications.

Objecttives This study investigated the effect of lifelong physical load from work on the development of knee osteoarthrosis (OA) leading to prosthetic surgely among men and women. Methods In a population-based case-referent study, men and women (N=625) who had had prosthetic surgery due to primary tibiofemoral OA were compared with referents (N=548) as to job titles and exposure to physical load in occupational work, housework, and leisure-time activities from 15 to 50 years of age. W~S U~~S Male forestry and construction workers, and both male and female farmers ran the highest risk of lmee OA. The men had considerably higher exposure to lifting at work, and also to jumps and vibration, than the women. Among the men there was an association between lifting at work [odds ratio (OR) 3.0,95% confidence interval (95% CI) 1.6-5.51, squatting or knee bending (OR 2.9,95% CI 1 . 7 4 . 9 ) , kneeling (OR 2.1,95% CI 1.4-3.3), and jumping (OR 2.7,95% CI 1 . 7 4 . 1 ) with knee OA. Exposure to physically demanding tasks at home, such as taking care of an elderly or handicapped person, was associated with knee OA among the women (OR 2.2,95% CI 1.3-3.6). C O~~C~U S~O~SWorking as a farmer or as a construction worker could be associated with the development of knee OA and lead to prosthetic surgery. Men and women differ in the quality and quantity of reported physical load and also in the strength of the risk estimates. A reduction of high physical load at work and at home could probably lower the risk of knee OA later in life.