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T Hakulinen

Publications and source records attributed to T Hakulinen.

At least 163 records · Page 9Linked to original sources
PubMed1987

Testing equality of relative survival patterns based on aggregated data.

The relative survival rate is defined as the ratio of the survival rate observed in a patient group under consideration to the survival rate expected in a group of people similar to the patient group at the beginning of the follow-up interval, with respect to all possible factors (e.g., age and sex) affecting survival, except the disease under study. Survival from cancer and other chronic diseases is often measured by this quantity, which is adjusted for the effect of mortality attributable to competing risks of death. In this paper, maximum likelihood ratio tests are constructed on the basis of aggregated data for testing the equality of relative survival rates between patient groups against proportional hazards and general alternative hypotheses. The tests are applied to the Finnish nationwide data on colon cancer patients with nonlocalized tumors as reported to the Finnish Cancer Registry. Simulation studies show that the maximum likelihood ratio tests compare favorably with alternative methods proposed earlier. Moreover, the maximum likelihood ratio tests are more extensive in coverage and are based on more applicable alternative hypotheses than the other test statistics. Finally, an extension to proportional hazards regression models of the relative survival rates is suggested.

Biometry↗
PubMed1986

Do the predictions for cancer incidence come true? Experience from Finland.

The observed occurrence of cancer in Finland in 1980 was compared with that predicted by extrapolation of the trends in cancer incidence by site in 1957 to 1968. The predictions had been constructed as 90% confidence intervals. Of the mutually exclusive 33 incidence predictions, 22 (67%) included the observed incidence rate. The incidence rate was successfully predicted for intestinal, pancreatic, and urinary cancers, as well as for lymphomas, whereas incidence forecasts concerning cancers of the lung, breast, and cervix uteri, and melanomas of the skin did not come true. The incidence of male lung cancer did not increase as was expected, breast cancer incidence increased even more than expected, and the decrease in the incidence of cervical cancer was steeper than expected. Because of failure in the population forecast, only 55% of the predictions (90% confidence intervals) for the numbers of new cancer cases included the observed number. For administrative purposes it would be important for the predictions to come true. On the other hand, the successes or failures of the predictions related to specific cancers may be used to study the effect of changes in etiologic factors, diagnostic methods, or the definition of cancer, as well as the effect of mass screening or other intervention measures upon the cancer incidence. Extrapolation as a method of forecasting cancer incidence is adequate as far as the control of random error is concerned when only short-term forecasts, ranging from 5 to 10 years, are needed.

Aged↗
PubMed1986

Global and regional mortality patterns by cause of death in 1980.

Mortality attributable to major causes of death around 1980 has been estimated for different regions in the world. The World Health Organization's mortality data bank has been employed to derive the rates for the developed areas in the world whereas for the developing areas, cause-specific mortality has been estimated on the basis of total mortality using a linear regression method. For the cause grouping chosen, infectious and parasitic diseases claim one third of all deaths in the world. Although diseases of the circulatory system and neoplasms are the two most common causes of death in the developed countries, more than 50% of all deaths in the world due to these causes occur in the developing world. Mortality due to injury and poisoning is--contrary to that due to the other main causes of death--almost independent of the level of development of the area. The results are aimed to assist the information back-up for health policies concerning the developing world.

Adolescent↗
PubMed1986

Mortality in relation to urinary characteristics in the very aged.

The value of urinary characteristics observed in a health survey of people aged 85 years or more was studied in a 5-year follow-up. Of the 561 aged people participating in the initial survey, 167 (30%) were alive after 5 years. Hematuria, pyuria, and albuminuria were associated with high mortality; urinary acidity was associated with low mortality. Positive bacterial staining, glucosuria, and specific gravity of urine were not related to the survival rate. Contrary to earlier observations, bacteriuria found in the urinary bacterial culture did not have any prognostic significance in respect of survival during the follow-up period. Judging from the results, the medical treatment of asymptomatic bacteriuria, with the aim of reducing the mortality of the very aged, appears to be unwarranted.

Aged↗
PubMed1986

Similar survival rates for rheumatoid and non-rheumatoid cancer patients.

The survival rate for cancer patients with rheumatoid arthritis was compared with that for non-rheumatoid cancer patients. This was accomplished by linking two nationwide Finnish data registers, the Social Insurance Institution's Population Register and the Finnish Cancer Registry. For 2012 of the 2062 rheumatoid patients with cancer diagnosed after the diagnosis of rheumatoid arthritis, the Cancer Registry was successfully searched for a non-rheumatoid of diagnosis of control patient who matched with respect to sex, age, year of diagnosis of cancer and location of the tumour (and also, for leukaemia, with respect to cell type). The 5-year relative survival rate for male rheumatoid patients was 21.2% and, for the control cancer patients, 25.4%. In females, the corresponding rates were 38.2% for the rheumatoid patients and 41.2% for the control patients (p less than 0.05). At some sites, particularly with leukaemia, the rates for the rheumatoid patients were lower than those for the control patients. The difference, however, only reached a 5% significance level for colorectal cancer in males. Rheumatoid arthritis and its treatment do not seem to have any appreciable effect on the survival of cancer patients.

Arthritis, Rheumatoid↗
PubMed1986

Trends in cancer incidence in the Nordic countries. A collaborative study of the five Nordic Cancer Registries.

Time trends and differentials in cancer incidence in the five Nordic countries, Denmark, Finland, Iceland, Norway and Sweden, were investigated, using material collected by the cancer registries in each country. The incidence at all sites combined and at 23 anatomical sites was studied by age, birth cohort and time period. The maximum lengths of the trends were used for each country. In Denmark the material comprised all the tumours diagnosed in 1943-1980, in Finland and Norway those diagnosed in 1953-1980, in Iceland those diagnosed in 1955-1980, and in Sweden those diagnosed in 1958-1980. For males the age-adjusted cancer incidence rates at all sites combined were highest in Denmark and Finland, and lowest in Sweden and Norway. In females the incidence was highest in Denmark and Iceland, and lowest in Finland. The rates increased slightly for both sexes. For cancer of the pancreas, Hodgkin's disease, acute leukaemia and childhood cancer (all sites combined) the rates in all the Nordic countries were similar every year. For cancers of the stomach, colon, breast, corpus uteri, ovary, prostate, testis, urinary bladder, melanoma of the skin and non-Hodgkin's lymphomas the trends were similar but on different levels. For cancers of the larynx and lung in males the rates in Finland decreased during the 1970s, whereas the rates were increasing in the other Nordic countries. For cancer of the rectum, the trend showed a decrease in Denmark but an increase in the other Nordic countries. For lip cancer the rate in Sweden was almost constant over time, but in Denmark, Finland and Norway a decrease occurred. For oesophageal cancer in males the rates decreased in Finland and Iceland in the 1970s, whereas in Denmark and Norway there was very little change, and in Sweden there was an increase in the rates. For cancer of the cervix uteri the rates started to decrease in Denmark, Finland, Iceland and Sweden in the mid-1960s, but in Norway not until some ten years later. The differentials between the countries were largest for cancers of the testis and thyroid, in which the highest incidence was five to six times as large as the lowest. For testicular cancer the rate was the highest in Denmark, for thyroid cancer in Iceland. For both of these cancers the rate was the lowest in Finland. Melanoma of the skin was the cancer with the most rapid increase in incidence with time in all the Nordic countries.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1985

Sauna, dust and migration as risk factors in lung cancer among smoking and non-smoking males in Finland.

To study possible causes of the high lung cancer incidence among Finnish males, the Finnish Cancer Registry and the Cancer Registry of Norway in 1962 performed a population survey covering smoking habits, occupational and residential history and, in Finland, sauna habits. The cohort of 4,475 Finnish men has now been followed up for incidence of lung cancer in 1964-1979. The relative importance of 3 factors--sauna baths, occupational exposure to dust, and migration to urban areas--was studied in different smoking categories. Among smokers of greater than or equal to 25 g/day, takers of frequent saunas (more than once a week) displayed some excess risk (RR 1.7). In smokers an increased risk was also found among those exposed to dust (RR 1.3), and those who had migrated to urban areas (RR 1.8, when compared to native urban population). Dust exposure and migration factors act synergistically with smoking. Migration was the only factor apart from smoking to show a substantial population-attributable risk, which amounted to 10%.

Dust↗
PubMed1985

Rheumatoid arthritis and cancer studies based on linking nationwide registries in Finland.

Two separate registries that cover the whole population of Finland have been linked in order to study the occurrence of cancer in patients with rheumatoid arthritis. The two registries involved were the Social Insurance Institution's Population Register, which collects information on medication for certain chronic diseases since 1967 including rheumatoid arthritis, and the Finnish Cancer Registry, which has data on all cancer patients in Finland since 1953. The 213,911 person-years' follow-up of 46,101 individuals with rheumatoid arthritis revealed 1,202 cases of cancer. The relative risk of cancer was 1.15 in males and 1.01 in females. The observed number of cases significantly exceeded that expected in Hodgkin's disease, non-Hodgkin's lymphomas, multiple myeloma, and leukemia. In general, the incidence of epithelial tumors was as expected. These findings were further supported by studying the occurrence of subsequent new primary cancers among patients with rheumatoid arthritis and cancer.

Arthritis, Rheumatoid↗
PubMed1985

A computer program package for relative survival analysis.

A computer program package has been constructed for use in patient survival analyses for chronic diseases based on aggregated data. The central concept of the analyses--the relative survival rate--is the ratio of the observed survival rate of the patients to the survival rate expected in a group in the general population similar to the group of patients at the beginning of the follow-up (interval), with respect to age, sex and calendar time. This quantity is used to measure patient survival adjusted for the effect of mortality attributable to the competing risks of death without employing information on causes of death of individual patients. The package contains three alternative methods of estimating the relative survival rates, two different ways of estimating the expectation of life for the patients, and five methods of testing the relative survival patterns using information on the whole follow-up period. Conventional survival and competing risk analysis can also be performed with the package. It is hoped that the package will facilitate standardization of statistical methodology and terminology in long-term survival studies for chronic diseases.

Aged↗
PubMed1985

Multiple tumor incidence in patients with rheumatoid arthritis or allied disorders.

The incidence of multiple malignant neoplasms in 55,279 patients with rheumatoid arthritis (RA) or allied disorders was studied by linking two separate nationwide data registers covering the whole Finnish population. The linking of the Social Insurance Institution's Population Register and the Finnish Cancer Registry resulted in 2106 cancer patients in whom both cancer (diagnosed in 1967-1978) and rheumatoid arthritis or allied disorders (diagnosed before cancer) were diagnosed. In 1974, the allied disorders (ankylosing spondylitis or systemic connective tissue diseases) accounted for 3.9% of all the diagnoses in the Social Insurance Institution's Population Register. The incidence of multiple neoplasms was slightly but not significantly higher in cancer patients with RA or allied disorders than in the general population or in all cancer patients taken together. The risk of leukemia was four times higher in the rheumatoid or allied disease cancer patients than in all the cancer patients. The results are consistent with previous results showing that the leukemia incidence in RA patients is higher than expected.

Adult↗
PubMed1985

Age dependence of the west/east gradient in cardiovascular mortality of Finnish males.

A cohort of 4 475 Finnish men was followed up during 1964-80 in order to study regional differences in mortality from cardiovascular diseases, especially ischaemic heart disease (IHD). The west/east gradient in cardiovascular mortality recorded in several previous studies was greatly age-dependent. The excess eastern risk was a feature of younger age groups; with increasing age the risk pattern was reversed. The risk factors in IHD in eastern Finland have an element which somehow accelerates the process of this disease.

Adult↗
PubMed1985

Formaldehyde exposure and respiratory and related cancers. A case-referent study among Finnish woodworkers.

A case-referent study was undertaken to investigate the associations between formaldehyde exposure and respiratory and related cancers. Fifty-seven such cancers from a retrospective cohort of male woodworkers formed the case group. They were matched by year of birth with 171 referents. Exposure to formaldehyde was assessed with job-exposure matrices. The median of the time-weighted average concentration was about 1 ppm, and the mean duration of exposure was 10 years among the exposed. Odds ratios (OR) were calculated for formaldehyde exposure (1.44), peak exposure to formaldehyde (1.26), and exposure to formaldehyde-containing wood dust (1.22). None of the values exceeded unity with statistical significance. Allowance was also made for a 10-year period from the onset of exposure. Birth year, cigarette smoking and exposure to wood dust, chlorophenols, pesticides, and terpenes were controlled by stratification. The adjusted ORs did not change appreciably. The highest OR was 1.95 for formaldehyde exposure without allowance for minimum latency, adjusted for exposure to terpenes. No exposure-response relation was observed for the level, duration, or dose (ppm-years) of formaldehyde exposure. The result is nonpositive and may be explained by absence of effect, by too short a follow-up, or by insufficient power for detecting a mild excess risk.

Adult↗
PubMed1983

Occupation and smoking as risk determinants of lung cancer.

The standardized incidence ratio (SIR) of lung cancer was determined for different occupational groups in Finland. The data on all cases of lung cancer diagnosed in Finland in age groups of 35-69 years in 1971-1975 were supplemented by information on occupation from the 1970 census (Central Statistical Office). The expected numbers of cases were based on the sex, age and occupation-specific numbers of person-years computed in the Central Statistical Office, and sex- and age-specific incidence rates of lung cancer among the economically active population (as defined 1 January 1971). Compared with the risk of the total economically active population, the relative risk of those not active (SIR) was 1.69 for men and 0.86 for women. Lower than expected relative risks were encountered among highly educated and white-collar male workers (religious, legal, pedagogical, medical, technical and administrative work), in sales work, transport service work and among farmers. High SIRs were found in mining and quarrying, forestry, woodworking (joiners), construction, painting and among unskilled workers. Among women the numbers of cases were small and only one significant SIR was obtained; the risk was lower than expected in farming. Data on the smoking habits of males in different main occupational categories in Finland show that variation between different occupational groups in the prevalence of smoking closely corresponds to that in the SIR for lung cancer (R = 0.96).

Adolescent↗
PubMed1983

A comparison of nationwide cancer survival statistics in Finland and Norway.

Nationwide cancer survival statistics published in Finland and Norway were compared. The results showed that there are cancer sites (e.g. stomach and lung) at which the 5-year relative survival rates are equal in both countries, but also many sites at which the survival figures differ (e.g., cancer of the breast and melanoma of the skin). Ideally, the differences in cancer survival between these countries could be used to study the effects of any differences in health care systems, (e.g., modes of treatment). Differences in cancer survival might also be used in the interpretation of cancer incidence figures. It was shown, however, that even with Finland and Norway, in which cancer registration and follow-up systems are relatively comparable and definitions and classifications criteria continually monitored, several factors complicate survival comparisons. These include distribution by histological type, exact location of the tumours, definitions and distributions of tumour stages, and finally definition of the cancer itself.

Adenocarcinoma↗