| 251. |
- Lissner, Lauren, 1956, et al.
(författare)
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Low-fat diets may prevent weight gain in sedentary women: prospective observations from the population study of women in Gothenburg, Sweden
- 1997
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Ingår i: Obesity Research. ; 5, s. 43-48
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Tidskriftsartikel (refereegranskat)abstract
- Department of Primary Health Care, Göteborg University, Sweden. The Population Study of Women in Gothenburg, Sweden is an ongoing prospective study of female residents who were recruited from the local registry in 1968-1969 when they were 38-60 years old. The data presented here were collected from 361 healthy women who underwent a baseline physical examination including a supplementary dietary history interview and returned for a second general health examination 6 years later. This report identifies a subgroup of 57 women who were sedentary during their leisure time and appear to have been particularly susceptible to gaining weight as a function of the fat content of their diets. Specifically, longitudinal analysis of body weights in the whole sample revealed a statistical interaction between leisure-time physical activity and habitual dietary fat intake (energy%), as reported at the baseline examination, in the prediction of subsequent weight change. Further stratified analysis suggested that weight changes were significantly dependent on dietary fat intake among the sedentary women only. High energy intake also predicted weight gain in the sedentary group, although the predictive value for a high-fat diet was of marginal significance after adjusting for total energy consumption. These results suggest that sedentary recreational activity plus a low-fat diet may have a combined contribution to weight change that is not equivalent to the sum of the separate effects. Such a synergy between two modifiable lifestyle factors seems highly relevant for prevention of obesity. PMID: 9061715 [PubMed - indexed for MEDLINE]
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| 252. |
- Lissner, Lauren, 1956, et al.
(författare)
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Monitoring the Obesity Epidemic into the 21st Century - Weighing the Evidence.
- 2013
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Ingår i: Obesity facts. - : S. Karger AG. - 1662-4033 .- 1662-4025. ; 6:6, s. 561-565
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Tidskriftsartikel (refereegranskat)abstract
- According to recent literature the obesity epidemic in adults and particularly in children seems to have stabilized or receded since the end of the 20th century [1,2]. Many of the encouraging trends toward stabilization have occurred simultaneously in different parts of the world. However, there may be some biases in the data being reported that could explain these trends, to which we will draw attention in the sections below. Besides statistical biases and distortions in the data itself, there may be interpretation biases of a less statistical nature. This paper is not intended to systematically review all publications on the course of the epidemic or discuss study-specific biases in detail, but rather intends to highlight the most relevant sources of bias while offering selected examples of such biases from the literature. We will first review several classic sources of bias in survey data describing secular trends in obesity, which have been frequently discussed in terms of how they might affect conclusions regarding the course of the obesity epidemic. In addition, we will describe sources of bias in what we are looking at and how we are looking at it, which may distort conclusions regarding the obesity epidemic.
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| 253. |
- Lissner, Lauren, 1956, et al.
(författare)
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OPEN about obesity: recovery biomarkers, dietary reporting errors and BMI
- 2007
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Ingår i: International Journal of Obesity. ; 31, s. 956-961
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Tidskriftsartikel (refereegranskat)abstract
- Department of Public Health and Community Medicine, Sahlgrenska Academy at Göteborg University, Sweden, and Research Unit for Dietary Studies at Institute of Preventive Medicine, Copenhagen University Hospital, Denmark. Lauren.lissner@medfak.gu.se OBJECTIVE: Obesity-related under-reporting of usual dietary intake is one of the most persistent sources of bias in nutrition research. The aim of this paper is to characterize obese and non-obese individuals with respect to reporting errors observed with two common dietary instruments, using energy and protein recovery biomarkers as reference measures. POPULATION AND METHODS: This report employs data from the Observing Protein and Energy Nutrition (OPEN) study. Analyses are based on stratified samples of 211 (57 obese) men and 179 (50 obese) women who completed 24-h recalls (24HR), food frequency questionnaires (FFQ), doubly labelled water (DLW) and urinary nitrogen (UN) assessments. RESULTS: In obese and non-obese subgroups, FFQ yielded lower energy and protein intake estimates than 24HR, although biomarker-based information indicated under-reporting with both dietary instruments. Gender differences in obesity-related bias were noted. Among women, the DLW-based energy requirement was 378 kcal greater in obese than in non-obese groups; the FFQ was able to detect a statistically significant portion of this extra energy, while the 24HR was not. Among men, the DLW-based energy requirement was 485 kcal greater in the obese group; however, neither FFQ nor 24HR detected this difference in energy requirement. Combining protein and energy estimates, obese men significantly over-reported the proportion of energy from protein using the 24HR, but not with the FFQ. In obese women, no significant reporting error for energy percent protein was observed by either method. At the individual level, correlations between energy expenditure and reported energy intake tended to be weaker in obese than non-obese groups, particularly with the 24HR. Correlations between true and reported protein density were consistently higher than for protein or energy alone, and did not vary significantly with obesity. CONCLUSION: This work adds to existing evidence that neither of these commonly used dietary reporting methods adequately measures energy or protein intake in obese groups. The 24HR, while capturing more realistic energy distributions for usual intake, may be particularly problematic in the obese. PMID: 17299385 [PubMed - indexed for MEDLINE]
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| 254. |
- Lissner, Lauren, 1956, et al.
(författare)
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Participation bias in longitudinal studies: experience from the Population Study of Women in Gothenburg, Sweden
- 2003
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Ingår i: Scandinavian Journal of Primary Health Care. ; 21, s. 242-247
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Tidskriftsartikel (refereegranskat)abstract
- Department of Primary Health Care, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. lauren.lissner@medfak.gu.se OBJECTIVE: To describe a cohort study of women receiving a series of comprehensive health examinations over 32 years. DESIGN: Longitudinal population study based on a randomised sample of the female population from defined age cohorts. SETTING: City of Göteborg, Sweden. SUBJECTS: Subjects were 38, 46, 50, 54 or 60 years old at the start of the study in 1968. Re-examinations were performed in 1974, 1982 and 1992. Non-participants in the most recent examination, initiated in 2000, were offered home visits. MAIN OUTCOME MEASURES: Participation, anthropometric and blood pressure changes. RESULTS: At the end of the 32-year follow-up, 64% of the original participants were alive, and low participation among survivors was a problem. An acceptable participation rate (71% of those alive) was obtained after home visits were offered. Surviving non-participants already had elevated cardiovascular risk factors at onset of the study in 1968, along with lower educational level and lower socioeconomic status. Home visited subjects were similar to non-participants with regard to anthropometry and blood pressure, but did not differ from participants with regard to social indicators. Thirty-two-year longitudinal data demonstrate clear ageing effects for several important variables, which should, however, be considered in the context of documented differences with non-participants at the baseline examination. CONCLUSIONS: Longitudinal studies in elderly populations provide important data on changes during the ageing process. However, participation rates decline for a number of reasons and generalisations should be made with care. Moreover, including home visits in the protocol can both increase participation and reduce participation bias in elderly cohorts. PMID: 14695076 [PubMed - indexed for MEDLINE]
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| 255. |
- Lissner, Lauren, 1956, et al.
(författare)
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Physical activity levels and changes in relation to longevity. A prospective study of Swedish women
- 1996
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Ingår i: American Journal of Epidemiology. ; 143, s. 54-62
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Tidskriftsartikel (refereegranskat)abstract
- Department of Primary Health Care, Göteborg University, Sweden. In 1968-1969, a population-based sample of Swedish women aged 38-60 years was recruited for a health survey, and 20-year survival was later ascertained from national registries. Occupational and leisure-time physical activity data from the baseline and 6-year follow-up examinations were evaluated in relation to all-cause mortality among 1,405 women who were initially free of major diseases. In comparison with being inactive, the mortality relative risk associated with being somewhat active was 0.28 (95% confidence interval 0.17-0.46) for occupational activity and 0.56 (95% confidence interval 0.39-0.82) for leisure-time activity. Being in the most active occupational or leisure activity category further decreased mortality risk to a minor extent. A within-subject decrease in leisure activity over 6 years was also a significant risk factor for all-cause mortality (relative risk = 2.07, relative to no change), although there was no evidence of a benefit from increasing physical activity levels. Since exclusion of early endpoints did not affect the associations in any significant way, underlying illness is unlikely to have played a major role in these analyses. It is concluded that decreases in physical activity as well as low initial levels are strong risk factors for mortality in women, and that their predictive value persists for many years. PMID: 8533747 [PubMed - indexed for MEDLINE]
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| 256. |
- Lissner, Lauren, 1956
(författare)
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Prospective Studies Collaboration. Age-specific relevance of usual blood pressure to vascular mortality: a meta-analysis of individual data for one million adults in 61 prospective studies.
- 2002
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Ingår i: The Lancet. - 0140-6736. ; 360, s. 1903-13
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The age-specific relevance of blood pressure to cause-specific mortality is best assessed by collaborative meta-analysis of individual participant data from the separate prospective studies. METHODS: Information was obtained on each of one million adults with no previous vascular disease recorded at baseline in 61 prospective observational studies of blood pressure and mortality. During 12.7 million person-years at risk, there were about 56000 vascular deaths (12000 stroke, 34000 ischaemic heart disease [IHD], 10000 other vascular) and 66000 other deaths at ages 40-89 years. Meta-analyses, involving "time-dependent" correction for regression dilution, related mortality during each decade of age at death to the estimated usual blood pressure at the start of that decade. FINDINGS: Within each decade of age at death, the proportional difference in the risk of vascular death associated with a given absolute difference in usual blood pressure is about the same down to at least 115 mm Hg usual systolic blood pressure (SBP) and 75 mm Hg usual diastolic blood pressure (DBP), below which there is little evidence. At ages 40-69 years, each difference of 20 mm Hg usual SBP (or, approximately equivalently, 10 mm Hg usual DBP) is associated with more than a twofold difference in the stroke death rate, and with twofold differences in the death rates from IHD and from other vascular causes. All of these proportional differences in vascular mortality are about half as extreme at ages 80-89 years as at ages 40-49 years, but the annual absolute differences in risk are greater in old age. The age-specific associations are similar for men and women, and for cerebral haemorrhage and cerebral ischaemia. For predicting vascular mortality from a single blood pressure measurement, the average of SBP and DBP is slightly more informative than either alone, and pulse pressure is much less informative. INTERPRETATION: Throughout middle and old age, usual blood pressure is strongly and directly related to vascular (and overall) mortality, without any evidence of a threshold down to at least 115/75 mm Hg.
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| 257. |
- Lissner, Lauren, 1956
(författare)
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Prospective Studies Collaboration. Cholesterol, diastolic blood pressure, and stroke: 13,000 strokes in 450,000 people in 45 prospective cohorts. Prospective studies collaboration
- 1995
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Ingår i: Lancet. ; 346, s. 1647-1653
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Tidskriftsartikel (refereegranskat)abstract
- Individual studies of stroke have not clearly answered two questions: on the relation, if any, between total blood cholesterol and stroke; and on how the strength of the relation between diastolic blood pressure and stroke varies with age. The associations of blood cholesterol and diastolic blood pressure with subsequent stroke rates were investigated by review of 45 prospective observational cohorts involving 450,000 individuals with 5-30 years of follow-up (mean 16 years, total 7.3 million person-years of observation), during which 13,397 participants were recorded as having had a stroke. Most of these were fatal strokes in studies that recorded only mortality and not incidence, but about one-quarter were from studies that recorded both fatal and non-fatal strokes. After standardization for age, there was no association between blood cholesterol and stroke except, perhaps, in those under 45 years of age when screened. This lack of association was not influenced by adjustment for sex, diastolic blood pressure, history of coronary disease, or ethnicity (Asian or non-Asian). However, because the types of the strokes were not centrally available, the lack of any overall relation might conceal a positive association with ischaemic stroke together with a negative association with haemorrhagic stroke. When the highest and the lowest of the six blood pressure categories were compared, the difference in usual diastolic blood pressure was 27 mm Hg (102 vs 75 mm Hg), and there was a fivefold difference in stroke risk. This fivefold difference was seen both in those with a pre-existing history of coronary heart disease and in those without it. The proportional difference in stroke risk, however, was more extreme in middle than in old age. Among those aged < 45, 45-64, and 65+ when screened, the differences in the relative risks of stroke (between the highest diastolic blood pressure category and a combination of the lowest two categories) were tenfold, fivefold, and twofold, respectively. However, because the absolute stroke risks are greater in old age, the absolute differences in the annual stroke rates showed an opposite pattern, being 2, 5, and 8 per thousand, respectively. This suggests that the effects of therapeutic blood pressure reductions should be assessed separately in middle age and in old age. PMID: 8551820 [PubMed - indexed for MEDLINE]
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| 258. |
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| 259. |
- Lissner, Lauren, 1956, et al.
(författare)
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Recall of physical activity in the distant past: the 32-year follow-up of the Prospective Population Study of Women in Göteborg, Sweden
- 2004
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Ingår i: American Journal of Epidemiology. ; 159 (3):Feb 1, s. 304-307
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Tidskriftsartikel (refereegranskat)abstract
- Institute of Community Medicine, Primary Health Care, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. Lauren.Lissner@medfak.gu.se It has been of interest to researchers in chronic disease epidemiology to determine whether elderly subjects can accurately recall their physical activity patterns in the distant past. As part of a 32-year follow-up of the Prospective Population Study of Women in Göteborg, Sweden, 433 participants currently aged 70-92 years recalled their leisure-time physical activity at the original examination in 1968, when they had been 38-60 years of age. Using a four-point scale, subjects were originally asked to describe leisure-time activity during the previous 12 months. Identical questions were asked in 2000 describing levels in 1968 and current levels. Subjects were more likely to overestimate their previous activity level than to underestimate it: 43.9% of women classified themselves consistently at both examinations; 48.7% overestimated and 7.4% underestimated their previous activity levels. Using current activity as a proxy for recalled levels did not improve the moderate agreement with activity as originally reported in 1968. The average magnitude of the recall bias (recalled minus original values) amounted to one half of a unit on the four-point scale and was not significantly associated with age or body mass index. In summary, systematic errors were observed in remote physical activity recalls by elderly women, who generally remembered being more active 32 years earlier than they had originally reported. Physical activity recall questionnaires for the distant past should be used with caution, particularly in older populations. PMID: 14742291 [PubMed - indexed for MEDLINE]
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| 260. |
- Lissner, Lauren, 1956, et al.
(författare)
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Secular increases in waist-hip ratio among Swedish women
- 1998
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Ingår i: International Journal of Obesity. ; 22, s. 1116-1120
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Tidskriftsartikel (refereegranskat)abstract
- Department of Internal Medicine, Sahlgrenska University Hospital, Göteborg University, Sweden. INTRODUCTION: Secular increases in obesity have been documented in numerous populations. However, little is known about trends in fat distribution. Because men and women with elevated waist-hip ratios (WHR) constitute a high cardiovascular risk group, it is relevant to document secular changes in WHR. This paper compares WHR in three cohorts of women, one cohort recruited in the late 1960s and the others after 12 y and 24 y intervals. SUBJECTS AND METHODS: In 1968-1969, a randomly selected sample of women aged of 38 y and 50 y, was given anthropometric examinations (n = 761, total). The same measurements were taken on representative cohorts aged 38 y and 50 y in 1980-1981 (n = 677) and 1992-1993 (n = 167). All analyses of trends in WHR as a function of time are age-specific and body mass index (BMI)-adjusted. RESULTS: An interesting feature of this population is that BMI was stable from 1968-1969 to 1992-1993. However, WHR increased significantly in those aged 38 y and 50 y, independent of BMI (P = 0.001, both ages). The source of these changes in WHR was a combination of increasing waist circumferences and decreasing hip circumferences. Skinfold measurements, taken only at the first two examinations, also increased significantly. CONCLUSIONS: This female population appears to have experienced some changes in body shape and composition. However, we cannot explain the increasingly centralized fat patterning by changes in BMI, subcutaneous skinfold thickness or those obesity-related aspects of the modern lifestyle that we were able to measure. PMID: 9822951 [PubMed - indexed for MEDLINE]
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