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M Koskenvuo

Publications and source records attributed to M Koskenvuo.

At least 73 records · Page 4Linked to original sources
PubMed2000

Relative effect of genetic and environmental factors on body height: differences across birth cohorts among Finnish men and women.

OBJECTIVES: This study examined the change in heritability of adult body height across birth cohorts in Finland. METHODS: In 1981, cross-sectional questionnaires were completed by 10,968 twin pairs born before 1958. The effect of genetic factors was estimated via genetic modeling. RESULTS: Heritability increased from the cohort born before 1929 (0.76, 95% confidence interval [CI] = 0.65, 0.88 in men; 0.66, 95% CI = 0.55, 0.77 in women) to that born in 1947 through 1957 (0.81, 95% CI = 0.73, 0.87 in men; 0.82, 95% CI = 0.75, 0.89 in women). CONCLUSIONS: Heritability of height increased across Finnish birth cohorts born in the first half of this century and leveled off after World War II. Environmental factors, compared with genetic factors, appear to be more important among women than men.

Adult↗
PubMed1999

Genetic predisposition, environment and cancer incidence: a nationwide twin study in Finland, 1976-1995.

Twin studies integrate genetic and environmental (including physical environment and life-style) information by comparing monozygotic and dizygotic twins for the occurrence of disease. Our objectives were to compare cancer incidence in twins with national rates and to estimate both the probability that co-twins of affected twins may develop cancer and the importance of genetic predisposition and environment in cancer development. The nationwide record linkage of the Finnish Twin Cohort Study, the Finnish Cancer Registry and the Central Population Register allowed the follow-up of 12,941 same-sexed twin pairs for incident primary cancers from 1976 to 1995. Zygosity was determined by use of a validated questionnaire in 1975. Methods included calculation of standardized incidence ratios and concordances and fitting of structural equation models. A total of 1,613 malignant neoplasms occurred in the cohort. The overall cancer incidence among twins resembled that among the general population. Monozygotic co-twins of affected twins were at 50% higher risk than were dizygotic co-twins. Based on genetic modeling, inherited genetic factors accounted for 18% (95% confidence interval 4-32%) of the liability in inter-individual variation in the risk of overall cancer, while non-genetic factors shared by twins accounted for 7% (0-16%) and unique environmental factors for 75% (65-85%). Our results appear to exclude a contribution greater than one-third for genetic predisposition in the development of cancer in the general population, thus pointing to the earlier confirmed substantial role of environment.

Adult↗
PubMed1999

Genetic factors and osteoporotic fractures in elderly people: prospective 25 year follow up of a nationwide cohort of elderly Finnish twins.

OBJECTIVE: To determine whether genetic factors partly explain variation in risk of osteoporotic fracture, the true end point of the osteoporosis problem. DESIGN: Prospective 25 year follow up of a nationwide cohort of elderly Finnish twins. SETTING: The Finnish twin cohort and the national hospital discharge register, covering the entire 5 million population of Finland. SUBJECTS: All same sex twin pairs born before 1946. The cohort contained 2308 monozygotic and 5241 dizygotic twin pairs (15 098 people) at the beginning of follow up. Main: outcome measure The number and concordance of osteoporotic fractures in the twin pairs, 1972-96. RESULTS: 786 cohort members sustained an osteoporotic fracture. In women, the pairwise concordance rate for fracture (that is, the relative number of twin pairs in whom the fracture affected both twins in a pair) was 9.5% (95% confidence interval 5.3% to 15.5%) in monozygotic pairs and 7.9% (5.2% to 11.4%) in dizygotic pairs. In men, the figures were 9.9% (4.4% to 18.5%) and 2.3% (0.6% to 5.7%). CONCLUSIONS: Susceptibility to osteoporotic fractures in elderly Finns is not strongly influenced by genetic factors, especially in elderly women. The traditional strategy for prevention of osteoporotic fractures-that is, increasing peak bone mass and preventing age related bone loss-should be changed to include new elements such as prevention of falls and protection of the critical anatomical sites of the body when a fall occurs.

Aged↗
PubMed1999

Nightmares: familial aggregation and association with psychiatric disorders in a nationwide twin cohort.

We quantified the genetic influences affecting the liability to nightmares, and the association between nightmares and psychiatric disorders in a community-based sample. In 1990, 1,298 monozygotic (MZ) and 2,419 dizygotic (DZ) twin pairs aged 33-60 years responded to a questionnaire study in the Finnish Twin Cohort. Structural equation modeling was used to estimate genetic and environmental components of variance in the liability to nightmares. Records on hospitalization and long-term antipsychotic medication were used to estimate the period prevalence of serious psychiatric disorders. Nightmares were reported more frequently in females both in childhood and as adults. The correlation between occurrence in childhood and as adults was 0.69 in males and 0.71 in females. Polychoric correlations of occurrence within the twin pairs were 0. 45 in MZ and 0.21 in DZ pairs in childhood, and as adults 0.39 and 0. 18, respectively. The best fitting genetic model was that specifying additive genetic and unshared environmental effects. The estimated proportion of genetic effects in childhood was in males 44% (95% confidence interval [CI] 35-52%) and in females 45% (95% CI 38-52%) of the phenotypic variance. As adults the values were in males 36% (95% CI 27-44%) and in females 38% (95% CI 31-45%). Nightmare frequency and psychiatric disorders were linearly associated. Among those with the most frequent nightmares odds ratios (95% CI) were 3. 67 (2.48-5.42) for childhood and 5.87 (4.08-8.45) for adults compared with those never having nightmares. Nightmares are quite a stable trait from childhood to middle age. There are persistent genetic effects on the disposition to nightmares both in childhood and adulthood. Nightmares are significantly associated with psychiatric disorders.

Adult↗
PubMed1999

Limits of self-report in assessing sleep terrors in a population survey.

Sleep terrors are less frequent compared to other parasomnias, and there are no prevalence studies on adults. We performed a questionnaire study in a well-defined population-based sample, the Finnish Twin Cohort. The study population consisted of 11,220 subjects aged 33-60 years, responding to questions on the frequency of sleep terrors in childhood and as adults. In the first questionnaire about 9% reported sleep terrors often or sometimes in childhood, and 3.5% at least once monthly as adults. However, in a second more-detailed questionnaire, only 1% of those with at-least-monthly attacks in adulthood presented with features compatible with the minimal diagnostic criteria for sleep terrors of the International Classification of Sleep Disorders. There was also a strong correlation between current occurrence of nightmares and the report of sleep terrors. Although a clinically definable entity, sleep terrors seem to be unknown to lay people, at least in Finland. Therefore, the use of single items or brief question series on sleep terrors may give inaccurate results in questionnaires. An interview of a person who has witnessed the nocturnal attack suspected to be sleep terror is essential because of the patient's impaired recall of the episode. Our results also support the general view that sleep terrors are rare in adults.

Adult↗
PubMed1999

Longitudinal analyses of the determinants of drinking and of drinking to intoxication in adolescent twins.

Genetic and environmental determinants of self-reported alcohol consumption were investigated in a sample of 2513 twin pairs who were first assessed at age 16 and were followed-up at age 17. At age 16, 77% of the sample was drinking, and 65% of drinkers reported drinking to intoxication. Both drinking and drinking to intoxication increased at the 1-year follow-up. Model fitting indicated that most of the variance in drinking initiation was due to shared environmental effects but that shared environmental effects were less important, and additive genetic effects were more important, in explaining frequency of drinking among subjects who had already initiated drinking. Similarly, shared environmental effects explained most of the variation in initiation of drinking to intoxication but were less important in explaining frequency of intoxication among subjects who had already initiated drinking to intoxication. The magnitude of genetic and environmental estimates for males and females did not differ significantly, but it was clear that either different genetic factors or different shared environmental factors were influencing males and females. For all drinking variables studied, shared environmental effects decreased from age 16 to age 17, while additive genetic effects increased from age 16 to age 17.

Adolescent↗
PubMed1999

Environmental factors in the development of obesity in identical twins.

OBJECTIVE: To study environmental factors promoting obesity when genetic factors are identical. DESIGN: Monozygotic (MZ) twins discordant for overweight were examined during a 3-day stay in an inpatient setting. SUBJECTS: The subjects were selected from the Finnish Twin Cohort. The study sample consisted of 23 healthy adult MZ twin pairs (14 female, nine male) with a difference of at least 3 kg/m2 in BMI. The mean BMI was 29.5 kg/m2 for the overweight twins and 22.9 kg/m2 for their lean co-twins. MEASUREMENTS: Interviews and standardized questionnaires were used to obtain information about energy and nutrient intake, eating behaviour, physical activity history, smoking and other background factors. RESULTS: The overweight co-twins had higher disinhibition scores (P = 0.007) and hunger scores (P = 0.005) in the 3-Factor Eating Questionnaire than their lean co-twins. Among women the mean daily energy intake was higher in the overweight twins than in their lean co-twins (8.8 vs 7.4 MJ; P = 0.045). In the twins discordant for smoking the mean BMI was higher in non-smokers than in smokers (BMI 29.7 +/- 4.4kg/m2 vs 23.8 +/- 3.1 kg/m2; P = 0.031). CONCLUSIONS: Difficulty in controlling eating in both sexes and high energy intake in women were related to overweight, independent of genetic background. Smoking explained the BMI difference among smoking discordant pairs. It is probable that individual twin pairs had different reasons behind the variation in weight gain resulting in non-significant intrapair differences in single obesity-promoting factors. Difference in living conditions (e.g. family-and work-related factors) may have promoted different living habits, especially eating behaviour, and may have led to different weight gain in identical twins.

Adult↗
PubMed1999

Clinical characteristics of migraine in a population-based twin sample: similarities and differences between migraine with and without aura.

OBJECTIVE: To look into clinical differences between migraine with and without aura in a population-based sample of migraineurs. BACKGROUND: Migraine presents in two major forms, migraine with and migraine without aura. With the exception of the aura phase, the clinical characteristics of these entities are very similar. Despite this, however, the recent epidemiological data underline differences between migraine with and without aura. We tried to examine whether other features besides the aura differ between these two major forms of migraine. METHODS: We studied 321 twins suffering from migraine with aura and 166 twins with migraine without aura from the population-based Finnish Twin Cohort. Migraine was diagnosed according to the criteria of the International Headache Society (IHS). Analysis was based on the combination of a mailed questionnaire and a telephone interview by a neurologist. Special attention was paid to differences between migraine with and without aura. RESULTS: Some qualities of headaches differed between IHS defined migraine with and without aura. Unilateral headache (Chi-squared p = 0.039) and photophobia (Chi-squared p = 0.010) were more typical for migraine with aura, while nausea was more typical for migraine without aura (Chi-squared p = 0.002). Duration of headache in migraine without aura was also longer than in migraine with aura (Mann-Whitney U-test 0.007). CONCLUSIONS: There are clinical differences between IHS defined migraine with and without aura; even the headache phase between the two entities differs. It is worthwhile distinguishing between them when looking for the elusive genes for these more common forms of migraine.

Adult↗
PubMed1999

Weight-loss attempts and risk of major weight gain: a prospective study in Finnish adults.

BACKGROUND: The effects of weight-loss attempts on long-term weight gain remain unclear. OBJECTIVE: The objective was to study prospectively how attempts to lose weight relate to future risk of major weight gain (>10 kg) and whether familial factors affect this relation. DESIGN: Participants in the Finnish Twin Cohort (3536 men and 4193 women aged 18-54 y at baseline) were followed up for 6-15 y. The role of familial factors was studied in 1705 twin pairs in this cohort who were discordant for weight-loss attempts at baseline. Baseline (1975) and follow-up (1981 and 1990) data-including weight, weight-loss attempts (dieting), and selected confounders-were obtained via mailed questionnaires. RESULTS: Average weight gain was at most weakly associated with weight-loss attempts. The risk of major weight gain for subjects attempting to lose weight at baseline was greatest among initially young (18-29 y) men (over 6 and 15 y, respectively-odds ratios: 2.01 and 1.74; 95% CI: 1.13, 3.57 and 1.11, 2.75) and middle-aged (30-54 y) women (over 6 and 15 y, respectively-2.43 and 1.52; 1.33, 4.42 and 1.06, 2.22) and persisted after potential confounders were controlled for. These risks decreased and became nonsignificant in the pairwise twin analysis, suggesting that the relation between dieting and subsequent major weight gain may also have a familial component. CONCLUSIONS: Weight-loss attempts may be associated with subsequent major weight gain, even when several potential confounders are controlled for. Genetic and familial factors may contribute to this association.

Adolescent↗
PubMed1999

Heart attacks and lower-limb function in master endurance athletes.

PURPOSE: Whether very vigorous physical activity bestows on the participant more health benefits or more adverse effects is unclear: we investigated whether men participating in competitive endurance sports in middle and old age are at increased risk of heart attacks as well as of lower-limb osteoarthritis and disability. METHODS: In our cohort study with an 11-yr follow-up, we studied 269 male orienteering runners (mean age 48.6 yr at baseline; range 37-61), who in 1984 were placed among the 60 best in their master orienteer age-class in Finland, and 188 male nonsmoking controls (mean age 50.4 yr; range 39-61) classified as healthy at 20 yr of age and without overt ischemic heart disease up until 1985. We followed mortality and studied the prevalence of questionnaire-reported physician-diagnosed diseases and disabilities at the end of the follow-up in late 1995. RESULTS: Two (0.7%) of the 269 runners and 10 (5.3%) of the 188 controls had suffered myocardial infarctions during the follow-up, the age-adjusted odds ratio (95% confidence interval) being 0.15 (0.03-0.67) in runners compared with controls (P = 0.0059). At follow-up, orienteering runners reported knee osteoarthritis and knee pain more often than did the controls, whereas the occurrence of hip osteoarthritis and hip pain did not differ. Disability due to hip or knee pain after the same everyday activities tended to be less in the runners. CONCLUSION: In top-level master endurance athletes having a long-term training background and participating in competitive endurance sports, the risk both of heart attack and of lower-limb disability is low.

Adult↗
PubMed1999

Clinical characteristics of migraine concordant monozygotic twin pairs.

OBJECTIVES: The aim of the study was to search for clinical differences between migraine with and without aura. MATERIALS AND METHODS: From a population-based Finnish Twin Cohort we studied 51 migraine concordant monozygotic twin pairs. RESULTS: There were 20 pairs concordant for migraine with aura, 6 pairs concordant for migraine without aura and 12 "mixed" pairs. In the remaining 13 pairs the aura of at least 1 twin could not be classified. All 20 migraine with aura pairs were concordant for visual aura and 19 for moderate or severe headache while all 6 pairs with migraine without aura were concordant for headache duration of 4 to 24 h, moderate or severe headache and nausea. The 12 "mixed" pairs had more often unilateral and pulsating headache compared to both the migraine with or without aura pairs. Overall individual migraine with aura twins had more photophobia (P = 0.032) and the migraine without aura twins more nausea (P = 0.025). CONCLUSIONS: The difference between migraine with and without aura is not explained entirely by genetical factors: 12 genetically identical twin pairs were discordant for the aura. The headache phase in migraine with and without aura is very similar, but not identical. Probably there are several and different liability loci for the migraine aura and the migraine headache. The distribution of these several loci along with acquired factors will decide whether the phenotype is migraine with or without aura.

Adult↗
PubMed1999

Evidence for involvement of the type 1 angiotensin II receptor locus in essential hypertension.

Components of the renin-angiotensin system play an important role in the normal regulation of blood pressure. We carried out a comprehensive genetic linkage study of the genes involved in the renin-angiotensin cascade in Finnish hypertensive twins and their affected siblings. We found no evidence for linkage between essential hypertension and the genes coding for renin, angiotensinogen, angiotensin-converting enzyme, or kallikrein 1 in the 329 hypertensive individuals of 142 families studied. In contrast, two intragenic markers for the type 1 angiotensin II receptor (AT1) showed some evidence for linkage in the total sample. A closer examination of this gene locus was carried out using subgroups of nonobese sibpairs with early onset of hypertension and uniform geographical origin. These stratifications yielded suggestive evidence for linkage of hypertension to the genetic area containing the AT1 gene, with a maximal multipoint logarithm of the odds (LOD) score of 2.9. A genetic association study carried out in an independent series of 50 hypertensive cases and 122 normotensive controls showed an increase in the frequency of the A1166-->C allele of the AT1 gene in the hypertensive individuals. In a novel variant of model-free multipoint linkage analysis allowing linkage disequilibrium in the calculations, an LOD score of 5.13 was obtained. Sequence analyses of the entire coding region and 848 bp of promoter region in the DNA sample on 8 index samples did not reveal previously unpublished sequence variations. The data provide evidence that a common genetic variant of the AT1 gene locus influences the risk of essential hypertension in the Finnish population.

Adult↗
PubMed1999

Joint-specific twin and familial aggregation of recalled physician diagnosed osteoarthritis.

In our three-stage questionnaire study we investigated patterns of twin and familial aggregation of osteoarthritis (OA) for commonly affected joints. The baseline questionnaire study of the Finnish Twin Cohort was performed in 1975. In 1990, 4095 twin pairs of the same gender born 1930-1957 responded to a questionnaire and reported whether they had OA diagnosed by a physician. In 1996 both twins of 266 pairs of which at least one had reported OA in 1990 responded to a detailed questionnaire on joint-specific OA, including family history of OA. In male pairs shared (non-genetic) familial effects accounted for 37% of the total variance in liability to OA and unshared environmental effects for 63%. In female pairs additive gene effects explained 44% of the variance in liability to OA, and unshared environmental effects for 36%. Familial aggregation of finger and knee OA was clearly higher than that of hip OA. Twin-pair discordance for OA was, to some extent, associated with body-mass index, occupational loading and trauma. Our results indicate that genetic effects may be modulated by sex or by environmental factors distributed differently between men and women. Based on our joint-specific data finger and knee joints are the most optimal targets for studies of genetic factors predisposing to the development of OA.

Adult↗
PubMed1999

Incidence and prevalence of asthma among adult Finnish men and women of the Finnish Twin Cohort from 1975 to 1990, and their relation to hay fever and chronic bronchitis.

STUDY OBJECTIVES: To examine the prevalence of asthma and hay fever, and the incidence and temporal relationships of asthma, hay fever, and chronic bronchitis among adult twins during a 15-year period. DESIGN: Prospective cohort study. PARTICIPANTS: A population of 11,540 Finnish adult men and women, initially 18 to 45 years of age, who returned a health questionnaire in 1975, 1981, and 1990 as part of the Finnish Twin Cohort study. METHODS: Age-standardized prevalences and cumulative incidences among individuals were calculated for asthma, hay fever, and chronic bronchitis. The incidence of asthma among subjects with and without hay fever or chronic bronchitis was analyzed in the entire cohort as well as in twin pairs discordant for incident asthma. RESULTS: The prevalence of asthma increased slightly from 1975 (2.0% in men and 2.2% in women) to 1990 (2.9% in men and 3.1% in women). The prevalence of hay fever showed a larger increase in men and women (from 6.8% and 9.8% to 11.8% and 15.3%, respectively). Compared with figures for 1976 to 1981, no significant increase in asthma incidence occurred from 1982 to 1990, whereas the incidence of hay fever was lower during the latter period among men (incidence rate ratio, 0.7; 95% confidence interval, 0.6 to 0.9) as was the incidence of chronic bronchitis among women (incidence rate ratio, 0.7; 95% confidence interval, 0.6 to 0.9). Hay fever and chronic bronchitis were usually diagnosed before asthma. Both diseases increased the risk of asthma significantly on the basis of analyses of all individuals and of discordant twin pairs. CONCLUSIONS: The pattern of increase in asthma and hay fever prevalence with time was similar, and hay fever was a strong predictor of asthma. These diseases showed no significant increase in incidence.

Adolescent↗
PubMed1999

Familial and socioregional environmental effects on abstinence from alcohol at age sixteen.

OBJECTIVE: This study identifies, in genetically informative data, familial and socioregional environmental influences on abstinence from alcohol at age 16. METHOD: Data are from FinnTwin 16, a population-based study of five consecutive birth cohorts of Finnish twins (N = 5,747 twin individuals), yielding 2,711 pairs of known zygosity. Measures of alcohol use, embedded into a health-habits questionnaire, were taken from earlier epidemiological research with nontwin Finnish adolescents. The questionnaire was administered sequentially to all twins as they reached age 16. Separate questionnaires, including measures of alcohol use and screening questions for alcohol problems, were received from 5,243 of the twins' parents. RESULTS: Abstinence from alcohol to age 16 exhibits very significant familial aggregation, largely due to nongenetic influences. Abstinence rates are influenced by socioregional variation, sibling interaction effects and parental drinking patterns. Sibling and parental influences are greater in some regional environments than in others: the relative likelihood that a twin abstains, given that the co-twin does, or that both parents do, is shown to be modulated by socioregional variation. CONCLUSION: Environmental contexts affect the likelihood of maintaining abstinence from alcohol to midadolescence, and socioregional variation modulates influences of siblings and parents. The results illustrate how genetically informative data can inform prevention research by identifying target variables for intervention efforts.

Adolescent↗
PubMed1999

Future hospital care in a population-based series of twin pairs discordant for physical activity behavior.

OBJECTIVES: This study investigated the association between physical activity behavior and morbidity, taking into account genetic selection. METHODS: Hospitalizations were followed from the beginning of 1977 to the end of 1986 in 710 same-sex healthy twin pairs discordant for leisure-time physical activity and in 151 pairs discordant for all physical activity at base-line in 1975. RESULTS: During the follow-up, among twin pairs discordant for leisure activity, the active member spent, on average, 43% fewer days in the hospital than the inactive member; the corresponding percentage was 55% among pairs discordant for all activity. CONCLUSIONS: Physically inactive behavior is associated with increased need for hospital treatments, even after genetic and other confounding factors are taken into account.

Adult↗