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L J Melton

Publications and source records attributed to L J Melton.

At least 19 recordsLinked to original sources
PubMed1992

Black-white differences in fracture rates.

To compare the incidence of all nonvertebral fractures between elderly blacks and whites, the authors conducted a retrospective cohort study among Tennessee Medicaid enrollees aged 65 years or more from 1987 through 1989. A previously validated computer algorithm identified 6,802 persons of black or white race with 7,645 new nonvertebral fractures. The incidence of all nonvertebral fractures in blacks was only half of that in whites. This finding persisted after the authors controlled for sex, age, and nursing home residence (relative risk = 0.4, 95% confidence interval 0.4-0.5). Rates were consistently lower among blacks within subgroups defined by these factors and for each of the 13 different fracture sites examined. The magnitude of the difference between blacks and whites in rates of all fractures combined and most site-specific fractures is similar to that previously reported for hip fractures. These consistent racial differences suggest a common underlying factor(s).

Age Factors↗
PubMed1992

Onset and disappearance of gastrointestinal symptoms and functional gastrointestinal disorders.

Functional gastrointestinal disorders, including the irritable bowel syndrome, account for up to 40% of referrals to gastroenterologists, but accurate data on the natural history of these disorders in the general population are lacking. Using a reliable and valid questionnaire, the authors estimated the onset and disappearance of symptoms consistent with functional gastrointestinal disorders. An age- and sex-stratified random sample of 1,021 eligible residents of Olmsted County, Minnesota, aged 30-64 years were initially mailed the questionnaire; 82% responded (n = 835). In a remailing to responders 12-20 months later, 83% responded again (n = 690). The age- and sex-adjusted prevalence rates per 100 for irritable bowel syndrome, chronic constipation, chronic diarrhea, and frequent dyspepsia were 18.1 (95% confidence interval (CI) 15.1-21.1), 14.7 (95% CI 11.9-17.4), 7.3 (95% CI 5.3-9.3), and 14.1 (95% CI 11.5-16.8), respectively, on the second mailing. Symptoms were not significantly associated with nonresponse to the second mailing; moreover, the estimated prevalence rates were not significantly different from the first mailing. Among the 582 subjects free of the irritable bowel syndrome on the first survey, 9% developed symptoms during 795 person-years of follow-up, while 38% of the 108 who initially had the irritable bowel syndrome did not meet the criteria after 146 person-years of follow-up. Similar onset and disappearance rates were observed for the other main symptom categories. While functional gastrointestinal symptoms are common in middle-aged persons and overall prevalence appears relatively stable over 12-20 months, substantial turnover is implied by the observed onset and disappearance rates; several potential sources of bias do not seem to account for this variation.

Adult↗
PubMed1992

Ankylosing spondylitis in Rochester, Minnesota, 1935-1989. Is the epidemiology changing?

OBJECTIVE: To determine trends in the incidence and clinical presentation of ankylosing spondylitis first diagnosed between 1935 and 1989 among residents of Rochester, Minnesota, and in the survival of the patients. METHODS: Population-based descriptive study. RESULTS: The overall age- and sex-adjusted incidence rate was 7.3 per 100,000 person-years (95% confidence interval 6.1-8.4). The rate tended to decline between 1935 and 1989, but there was little change in the age at symptom onset or diagnosis over the 55-year study period. Overall survival was not decreased up to 28 years following diagnosis. CONCLUSION: These data indicate that there is a constancy in the epidemiologic characteristics of ankylosing spondylitis and suggest that previously study results indicating changes may have been due to biases in patient selection and study design.

Adolescent↗
PubMed1992

Incidence of clinically diagnosed vertebral fractures: a population-based study in Rochester, Minnesota, 1985-1989.

Vertebral fractures are the classic hallmark of osteoporosis, yet little is known of their epidemiology. The incidence of clinically diagnosed vertebral fractures was therefore directly assessed in the predominantly white (European descent) population of Rochester, Minnesota. Altogether, 341 Rochester residents were radiologically diagnosed for the first time with one or more vertebral fractures in the 5 year study period, 1985-1989. The overall age- and sex-adjusted incidence rate was 117 per 100,000 person-years (95% CI, 105 to 130). The age-adjusted rate in women (145 per 100,000 person-years) was almost twice that in men (73 per 100,000 person-years). Of all fractures, 47 (14%) followed severe trauma, 282 (83%) followed moderate or no trauma, and 12 (3%) were pathologic. Incidence rates for fractures following moderate trauma were higher in women than in men and rose steeply with age in both genders. In contrast, fractures following severe trauma were more frequent in men, and their incidence increased less with age. These Rochester rates are greater than those previously reported from studies in Britain and Sweden but lower than the incidence rates extrapolated from a prevalence study in this population.

Adult↗
PubMed1992

Is caffeine consumption a risk factor for osteoporosis?

High caffeine consumption has been proposed as a risk factor for osteoporotic fracture, but the evidence associating high caffeine intake with low bone density is inconsistent. We therefore examined the influence of caffeine consumption on bone mineral at six skeletal sites in an age-stratified random sample of white women residing in Rochester, Minnesota. After age adjustment, there was no association between overall caffeine consumption and bone mineral at five of the six sites. In the femoral shaft, however, there was a statistically significant interaction between age and caffeine consumption so that high caffeine intake was associated with slight reductions in bone mineral among elderly subjects but with modestly increased bone mineral at younger ages. When caffeine intake was categorized by source, no consistent influence of coffee, tea, or other caffeinated beverage consumption could be detected on bone mineral. Caffeine intake was, however, positively associated with cigarette smoking and alcohol consumption. After adjusting for age, caffeine consumption was not correlated with biochemical indices of bone turnover, circulating concentrations of estradiol and estrone, or other dietary and musculoskeletal variables. These data suggest that caffeine intake in the range consumed by a representative sample of white women is not an important risk factor for osteoporosis. Among elderly women, however, in whom calcium balance performance is impaired, high caffeine intake may predispose to cortical bone loss from the proximal femur.

Adult↗
PubMed1992

Risk of fractures in patients with pernicious anemia.

In a series of postmenopausal women previously studied by our group, pernicious anemia was associated with reduced bone mineral density of the spine and with vertebral fractures. To determine whether osteoporotic fractures represent an important clinical problem for such patients, we conducted a population-based retrospective cohort study of all Rochester, Minnesota residents newly diagnosed with pernicious anemia from 1950 through 1979. These 131 individuals were followed through the inpatient and outpatient records of all medical care providers in the community for 1550 person-years. In comparison with fracture rates from the general community, patients with pernicious anemia had a 1.9-fold increase in proximal femur fractures, a 1.8-fold increase in vertebral fractures, and a 2.9-fold increase in distal forearm fractures (all p less than 0.05). Increases in the risk of proximal humerus and pelvis fractures were not statistically significant. Clinicians should be aware that pernicious anemia is associated with an increased risk of osteoporotic fractures, but the mechanism is unknown.

Adult↗
PubMed1992

Appendicular bone mineral and a woman's lifetime risk of hip fracture.

Appendicular bone mass is inversely related to the risk of hip fracture in short-term prospective studies, but hip fractures typically occur about 30 years after menopause. We developed a model that estimates a woman's lifetime risk of hip fracture based on measurement of radial bone mass at age 50 using short-term prospective data relating bone mass to hip fracture, the correlation between bone mass at age 50 and later years, the age-specific incidence of hip fracture and mortality, and prospective data about bone mass and mortality. We estimate that a 50-year-old white woman has a 19% lifetime risk of hip fracture if her radial bone mass is at the 10th percentile for her age and an 11% lifetime risk if her bone mass is at the 90th percentile. Improved measurement techniques that have a higher predictive value for hip fracture in short-term studies could substantially increase this gradient of lifetime risk and therefore be more clinically useful.

Aged↗
PubMed1992

Perspective. How many women have osteoporosis?

Osteoporosis is widely viewed as a major public health concern, but the exact magnitude of the problem is uncertain and likely to depend on how the condition is defined. Noninvasive bone mineral measurements can be used to define a state of heightened fracture risk (osteopenia), or the ultimate clinical manifestation of fracture can be assessed (established osteoporosis). If bone mineral measurements more than 2 standard deviations below the mean of young normal women represent osteopenia, then 45% of white women aged 50 years and over have the condition at one or more sites in the hip, spine, or forearm on the basis of population-based data from Rochester, Minnesota. A smaller proportion is affected at each specific skeletal site: 32% have bone mineral values this low in the lumbar spine, 29% in either of two regions in the proximal femur, and 26% in the midradius. Although this overall estimate is substantial, some other serious chronic diseases are almost as common. More importantly, low bone mass is associated with adverse health outcomes, especially fractures. The lifetime risk of any fracture of the hip, spine, or distal forearm is almost 40% in white women and 13% in white men from age 50 years onward. If the enormous costs associated with these fractures are to be reduced, increased attention must be given to the design and implementation of control programs directed at this major health problem.

Adult↗
PubMed1992

Secular trends in the incidence of postmenopausal vertebral fractures.

Several studies suggest secular increases in hip fracture incidence through this century, but little is known about such trends for vertebral fracture. We have examined changes in the incidence of clinically ascertained vertebral fractures among Rochester, Minnesota residents aged 35-69 years, that were first diagnosed between 1950 and 1989. Our results indicate no overall increase in incidence over the 40-year period. Categorization of fractures according to the level of preceding trauma, however, revealed a significant increase in the incidence of fractures following moderate trauma among women aged 60-69 years. This increase occurred between 1950 and 1964, and leveled off thereafter. Rates for severe trauma fractures among postmenopausal women, and for vertebral fractures from any cause among younger men and women, remained stable. The rise in moderate trauma fractures in postmenopausal women paralleled that for hip fractures in Rochester and began to plateau at around the same time. It might have resulted from increased diagnosis of vertebral fractures, but the increase in hip fracture incidence is inconsistent with this explanation. An increase in the prevalence of osteoporosis, however, might account for the trend in both types of fractures.

Adult↗
PubMed1992

Hip fractures in the elderly: a world-wide projection.

Hip fractures are recognized to be a major public health problem in many Western nations, most notably those in North America, Europe and Oceania. Incidence rates for hip fracture in other parts of the world are generally lower than those reported for these predominantly Caucasian populations, and this has led to the belief that osteoporosis represents less of a problem to the nations of Asia, South American and Africa. Demographic changes in the next 60 years, however, will lead to huge increases in the elderly populations of those countries. We have applied available incidence rates for hip fracture from various parts of the world to projected populations in 1990, 2025 and 2050 in order to estimate the numbers of hip fractures which might occur in each of the major continental regions. The projections indicate that the number of hip fractures occurring in the world each year will rise from 1.66 million in 1990 to 6.26 million by 2050. While Europe and North America account for about half of all hip fractures among elderly people today, this proportion will fall to around one quarter in 2050, by which time steep increases will be observed throughout Asia and Latin America. The results suggest that osteoporosis will truly become a global problem over the next half century, and that preventive strategies will be required in parts of the world where they are not currently felt to be necessary.

Adult↗
PubMed1992

Prevalence of gastrointestinal symptoms in the elderly: a population-based study.

The prevalence of chronic gastrointestinal symptoms and the irritable bowel syndrome (IBS) in the elderly, and their impact on health, is largely unknown. The prevalence of symptoms compatible with IBS was estimated in a representative sample of elderly community residents, and the impact of these symptoms was determined on presentation for health care. An age- and sex-stratified random sample of noninstitutionalized Olmsted County, Minnesota, residents aged 65-93 years were mailed a valid questionnaire; 77% responded (n = 328). The age- and sex-adjusted prevalence (per 100 persons) of frequent abdominal pain was 24.3 [95% confidence interval (CI), 19.3-29.2]. Chronic constipation and chronic diarrhea had prevalences of 24.1 (95% CI, 19.1-29.0) and 14.2 (95% CI, 10.1-18.2), respectively. Fecal incontinence more than once a week was reported in 3.7 per 100 (95% CI, 1.6-5.9). The prevalence of symptoms compatible with IBS (greater than or equal to 3 Manning criteria with frequent abdominal pain) was 10.9 per 100 (95% CI, 7.2-14.6). Among the subjects sampled who had abdominal pain, chronic constipation, and/or chronic diarrhea (n = 152), only 23% had seen a physician for pain or disturbed defecation in the prior year, and this behavior was poorly explained by the symptoms. It is concluded that complaints consistent with functional gastrointestinal disorders are common in the elderly, but symptoms are a poor predictor of presentation for medical care.

Abdominal Pain↗
PubMed1992

Osteoporosis and calcification of the aorta.

In an age-stratified random sample of 200 Rochester, Minnesota women, the prevalence of aortic calcification rose with aging, as did the prevalence of vertebral fractures, while bone mass fell. The statistically significant positive association of aortic calcification with vertebral fractures and the negative associations with bone mass at six skeletal sites were mainly accounted for by age. After age-adjustment, the only association remaining was a negative one between calcified aortic plaques and bone mineral density (BMD) of the lumbar spine (P < 0.05). Aortic calcification was not associated with any measures of calcium metabolism, after adjusting for age, except for a slight negative association between linear aortic calcifications and 25(OH) vitamin D levels (P < 0.05). BMD values of the lumbar spine were somewhat greater than predicted for age in women with severe aortic calcification, but similar findings were seen at other skeletal sites and none of the differences was statistically significant. While overestimation of bone mass was generally minimal, severe aortic calcification may distort lumbar spine assessments in a minority of postmenopausal women.

Adult↗
PubMed1992

Increasing incidence of pancreatic cancer among women in Olmsted County, Minnesota, 1940 through 1988.

To determine trends in the incidence of pancreatic cancer and associated survival, we conducted a population-based study in Olmsted County, Minnesota. From 1940 through 1988, 219 residents of Olmsted County (120 men and 99 women) were diagnosed as having exocrine pancreatic cancer. All patients were Caucasians, and 92% had a histologically confirmed diagnosis. The mean annual adjusted incidence of pancreatic cancer per 100,000 population was 8.5 overall (11.3 for men and 6.6 for women). During the course of the study, the incidence rates increased in women (P < 0.05) and in both genders combined (P = 0.06) but not in men (P = 0.4). The male:female ratio decreased from approximately 2:1 for 1940 through 1949 to 1.5:1 for 1980 through 1988. The incidence was significantly associated with increasing age (P < 0.001) and male gender (P < 0.001) but not calendar period (P = 0.19). The overall median duration of survival was 2.8 months. The 1-year survival rate was only 14%, and no patient lived for more than 55 months after pancreatic cancer was diagnosed. Men and women had similar survival rates. The increased incidence of pancreatic cancer among women may be due in part to the increasing life span of women and the increasing occurrence of pancreatic cancer in the aged.

Adult↗
PubMed1992

Fracture risk in patients with parkinsonism: a population-based study in Olmsted County, Minnesota.

In this population-based retrospective cohort study, the 138 Olmsted County, Minnesota residents first diagnosed with Parkinson's disease during 1967-79 were matched by age and sex to an equal number of control subjects from the community. Fractures were assessed through review of each subject's complete (inpatient and outpatient) medical records. At the time of diagnosis, County residents with parkinsonism were no more likely to have a history of selected fractures than control subjects (32% in each group). Subsequently, 33% of cases and 20% of controls experienced one or more new fractures during 696 person-years of follow-up (p = 0.008). The greatest increase in risk was seen for proximal femur fractures, confirming previous case-control studies. By 10 years after diagnosis, an estimated 27% of the parkinsonism cohort had experienced a new hip fracture. The pattern of fractures that was observed suggested that the increased risk was due more to specific types of falls than to disuse osteoporosis.

Aged↗
PubMed1992

Hospitalization with vertebral fracture among the aged: a national population-based study, 1986-1989.

Whereas fractures related to osteoporosis have become a pressing public health concern, relatively few epidemiologic studies have focused on vertebral fractures. To shed further light on the occurrence of this injury, we collected data from the Health Care Financing Administration on 151,986 discharges listing a diagnosis of vertebral fracture over a 4-year period. After adjusting for age, white women experienced the highest rates of discharge, at 17.1 per 10,000 per year, followed by white men (9.9 per 10,000), black women (3.7 per 10,000), and black men (2.5 per 10,000). Among white women, discharge rates rose exponentially from 5.3 discharges per 10,000 population at age 65 to nearly 47.8 per 10,000 at age 90. White men, black women, and black men experienced less dramatic age-related increases in discharge rates. The similarity of these patterns to discharge rates for hip fracture suggests that the race-sex differences in vertebral fracture discharge rates may be due to differences in the incidence of vertebral fracture.

Aged↗