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The associations between serum alpha-tocopherol, beta-carotene, retinol, retinol-binding protein, and selenium levels and the subsequent occurrence of different cancers of low incidence were investigated in a nested case-control study of 39,268 men and women participating in the Social Insurance Institution's Mobile Clinic Health Examination Survey in Finland. During follow-up from the baseline in 1968-1972 to the end of 1977, a total of 115 cancers of the lip, oral cavity, pharynx, larynx, esophagus, liver, gallbladder, kidney, urinary bladder, brain, and skin were reported to the nationwide Finnish Cancer Registry. Alpha-tocopherol, beta-carotene, retinol, retinol-binding protein, and selenium concentrations were determined from stored serum samples collected from these cancer cases and matched controls at baseline. Several sites indicated an elevated risk of cancer at low levels of the serum variables, although only a few of these associations were statistically significant. Only melanoma patients had significantly lower serum alpha-tocopherol and beta-carotene levels than corresponding controls. Since the numbers of cancer cases were small, no firm conclusions can be drawn from these results until they have been confirmed in studies based on larger cohorts or on pooled data from several small samples.

Prevalence and incidence of known diabetes mellitus in Finnish subjects aged 30 years or over in 1970-1987 were investigated using a nationwide register of drug recipients and four population surveys. On the basis of the drug-register data, the prevalence of drug-treated diabetes in men increased from 1.5% in 1970 to 2.8% in 1987. In women, the prevalence increased from 2.1% in 1970 to 3.0% in 1979 and declined thereafter slightly to 2.7% in 1987. The increase in the prevalence of drug-treated diabetes was mainly due to the increase of diabetes in the age groups 60 years and older. The prevalence of all known diabetic subjects in the population studies increased from 2.1% in the health examination survey of 1966-1972 (n = 38,676) to 3.5% in the interview survey of 1976 (n = 10,657) and to 4.5% in the health examination survey of 1979-1980 (n = 7,217) but decreased to 3.3% in the interview survey in 1987 (n = 9,522). The increased prevalence of obesity in men and better survival may be important factors contributing to the increasing prevalence rates of diabetes in Finnish subjects aged 30 years and over.

From 1968 to 1977, the association between the level of vitamin A in serum and the subsequent incidence of cancer was examined in a longitudinal study of 36,265 persons initially aged 15-99 years in 25 population groups in Finland. During a mean follow-up of 8 years, 766 cancers were diagnosed. Serum retinol, retinol-binding protein, and beta-carotene levels were measured from frozen serum samples (stored at -20 degrees C) drawn from these persons before the start of follow-up and from 1,419 controls matched for sex, age, and place of residence who did not develop cancer during follow-up. The mean level of serum retinol among the cancer cases was 645 micrograms/liter for men and 587 micrograms/liter for women. The corresponding levels in the controls were 3.3% and 2.8% higher. There was an inverse gradient between serum retinol level and the occurrence of cancer among men. This association was, however, mainly concentrated in the first 2 years of follow-up. The mean level of serum beta-carotene was 72.3 micrograms/liter among male cases and 119.5 micrograms/liter among female cases. The corresponding levels of the controls were 14.0% and 5.5% higher. The differences were particularly clear with regard to lung cancer. These findings suggest that the association between retinol and cancer may be due to preclinical cancer and that there may be an association between beta-carotene and cancer.

The association between serum alpha-tocopherol levels and the subsequent incidence of cancer was investigated in a longitudinal study of 21,172 men initially aged 15-99 years in six geographic areas in Finland. The baseline examination was conducted in 1968-1972, and during the follow-up of 6-10 years, 453 cancers were diagnosed. The serum alpha-tocopherol levels were measured from stored serum samples from these men and from 841 male controls, matched for municipality and age, who did not develop cancer during the follow-up. The mean levels of serum alpha-tocopherol among the cancer cases and controls were 8.02 and 8.28 mg/liter, respectively. A high serum alpha-tocopherol level was associated with a reduced risk of cancer. The relative risk of cancer in persons in the two highest (threshold 8.70 mg/liter) quintiles of serum alpha-tocopherol was 0.64 (95 per cent confidence interval = 0.49-0.85) in comparison with those in the three lowest quintiles. The association was strongest for the combined group of cancers unrelated to smoking and varied between subgroups of the study population as well as between different cancers. The association persisted when adjusted for serum cholesterol, serum vitamin A, serum selenium, and various confounding factors. It also persisted when subjects with possible signs of cancer at the time when the blood samples were drawn or with cancers diagnosed during the first two years of follow-up were excluded. These findings agree with the hypothesis that high vitamin E intake protects against cancer.

Circulating thyroglobulin antibodies (TgA) were detected in 7.9 % and thyroid microsomal antibodies (MsA) in 25.8 % of a sample of 507 subjects in the adult population of southern Finland when titres as low as 1/5 for TgA and 1/10 for MsA were included. Both antibodies were measured by passive haemagglutination techniques. The prevalence of high titres was 0.6 % for TgA (≥ 1/25 000) and 4.2% for MsA (≥ 1/100 000). Eightyeight per cent of the TgA positive subjects also had MsA. The MsA titres were usually markedly higher than those of TgA in the same subjects.Serum thyrotrophin (TSH), cholesterol and triglycerides were measured in 123 euthyroid subjects with thyroid antibodies and no history of thyroid diseases, and in controls matched for age and sex. Serum TSH was elevated in 31 % of the TgA positive subjects and the mean TSH concentration was significantly above that of the controls. All 3 subjects with high TgA titres also had elevated TSH levels. Serum TSH concentration was increased also in 25 % of those with MsA and the mean TSH value was significantly above the control level. High MsA titres were found in 19 subjects and the serum TSH was elevated in 10 of them (53%). The prevalence of symptomless autoimmune thyroiditis (SAT) was 2 and 5 %, of the population when high titres of either TgA or MsA, respectively, and elevation of serum TSH was used as criteria. This fits with our previous observations. There was no difference in serum cholesterol or triglycerides in the TgA or MsA positive subjects or in the corresponding matched controls.

The reference values for gamma-glutamyltransferase (GT), aspartate aminotransferase (ASAT) and alkaline phosphatase (AFOS) activities in serum have been produced on the basis of measurements done in the Mini-Finland Health Survey. A representative sample of all Finns aged 30 years or over comprised 8000 persons, of whom 99.2% participated in the actual health survey. Every effort was made to obtain reference values for the healthy ambulatory population. Three separate health-derived selection criteria were used to obtain such reference values for the above-mentioned enzymes: those based on the available literature, with minor modifications, the recommendations published by the Committee on Reference Values of the Scandinavian Society for Clinical Chemistry and Clinical Physiology, criteria that were obtained after subgroup comparisons of the obtained data, where all the factors affecting the enzyme levels were identified. The recommendations of the Expert Panel on Theory of Reference Values (1987) were strictly adhered to in the statistical analyses. The distribution of the serum activity of GT was very skewed. The overall intervals for men and women were 5.1-1460 and 4.7-748 U/l, respectively. The frequency distributions could be transformed to the normal ones logarithmically. The 95% inner reference intervals for GT in the three groups were 7-76, 7-65, and 8-57 U/l for men and 6-35, 6-30 and 6-32 U/l for women, respectively. For ASAT the full intervals of the enzyme levels in serum were 2.6-770 U/l for men and 8.3-172 U/l for women. After logarithmic transformation the respective reference intervals in the three selection groups were 14-42, 14-40 and 13-39 U/l for men and 13-33, 12-31 and 13-33 U/l for women. The full intervals of AFOS were 47.5-2755 and 5.4-816 U/l for men and women, respectively; after the logarithmic transformation the reference intervals of the three selection groups were 98-267, 97-254 and 97-264 U/l for men and 77-265, 75-231 and 75-250 U/l for women, respectively.