L. Joseph Melton

Risk factors for spinal osteoporosis in men

Risk factors for vertebral fractures due to osteoporosis were evaluated in 105 consecutive male patients over a four-year period. An equal number of men with Pagets disease, matched by age, who concurrently attended the same subspecialty clinic served as control subjects. The relative risk for osteoporosis, estimated by the odds ratio, was increased among those who smoke cigarettes (relative risk = 2.3; p = 0.01), drank alcoholic beverages (relative risk = 2.4; p = 0.02), or had an associated medical disease known to affect calcium or bone metabolism (relative risk = 5.5; p less than 0.001). Obesity was protective (relative risk = 0.3; p less than 0.001). As assessed by a multiple logistic model, the risk associated with smoking and drinking increased with age. The effects of these four major risk factors were largely independent of one another and were cumulative. Thus, spinal osteoporosis in men is frequently associated with recognizable risk factors, some of which are potentially remediable.

Fine-needle aspiration biopsy of thyroid nodules: Impact on thyroid practice and cost of care

We studied the impact of fine-needle aspiration biopsy on the management of patients with solitary thyroid nodules. Sixty-four patients were examined before the introduction of fine-needle aspiration biopsy, and 147 patients were examined after its introduction. The percentage of patients who underwent thyroid operation decreased from 67 percent to 43 percent, while the yield of carcinoma increased from 14 percent to 29 percent. Cost of medical care per patient declined by 25 percent. The results suggest that fine-needle aspiration biopsy provides valuable information to assist in the selection for surgery of patients with solitary nodules. Fine-needle aspiration appears to be safe, reliable, and cost-effective. The merits of the technique commend it for routine use in the evaluation of thyroid nodules.

Assessment of Functional Gastrointestinal Disease: The Bowel Disease Questionnaire

A need exists for a self-report questionnaire that reliably and accurately measures symptoms and that distinguishes patients with functional gastrointestinal disease from those with other conditions. We have developed such an instrument, the bowel disease questionnaire, and herein describe details of its discriminatory validity. Data from 399 subjects were analyzed. Patients with gastrointestinal symptoms were ultimately diagnosed as having functional gastrointestinal disease (82 with the irritable bowel syndrome and 33 with functional dyspepsia) or organic gastrointestinal disease (N = 101). There were 145 healthy control subjects and 38 patients with a psychiatric disease, somatoform disorder (which includes those with a diagnosis of hypochrondriasis, psychogenic pain, and somatization or conversion disorder). All subjects completed the questionnaire before undergoing an independent diagnostic assessment by experienced physicians. Functional gastrointestinal disease could be distinguished from organic disease, somatoform disorder, and health by using models derived from logistic discriminant analysis. With use of these models, the estimated probability of functional gastrointestinal disease was then calculated. Descriptive symptom scores were of less value than the scores derived from the data sets by logistic discriminant analysis. Age did not significantly affect the responses to the questionnaire items. We conclude that, in the population studied, the bowel disease questionnaire is a valid measure of symptoms of functional gastrointestinal disease, and this instrument may have clinical and research applications.

A comparison of the Rome and Manning criteria for case identification in epidemiological investigations of irritable bowel syndrome

Abstract OBJECTIVE: The aim of this study was to estimate the prevalence of irritable bowel syndrome using different standard definitions (Rome and Manning criteria) and to determine the degree of agreement between these definitions. METHODS: A population-based, cross-sectional survey study was conducted by mailing a valid, reliable questionnaire to an age- and gender-stratified random sample of residents of Olmsted County, MN, aged 30–69 yr. The threshold for a positive diagnosis of irritable bowel was varied from two to four of the six Manning criteria and from two to three of the five defecation disorders in the Rome criteria. Unadjusted as well as age- and gender-adjusted prevalence rates were calculated for each of the five definitions of IBS. Percent agreement and κ statistics were calculated to assess agreement between the definitions. RESULTS: Questionnaires were returned by 643 of 892 eligible subjects (72% response rate). The age- and gender-adjusted prevalence of IBS varied from 20.4% using a threshold of two symptoms in the Manning criteria to 8.5% using a threshold of three defecation disorders in the Rome criteria. The percent agreement for each comparison of Manning and Rome definitions was always >90%. The κ values ranged from 0.55 to 0.78, with the best agreement occurring between a threshold of three symptoms of Manning and two defecation disorders in Rome. CONCLUSIONS: The prevalence of IBS varied substantially depending on the specific definition of IBS used. The range of prevalence estimates in Olmsted County was similar to other published figures when IBS definition was accounted for. These findings are useful in interpreting epidemiological and clinical studies of IBS.

Gallstone Pancreatitis and the Effect of Cholecystectomy: A Population-Based Cohort Study

Although an association between gallstones and pancreatitis has been recognized for almost 100 years, the risk of acute pancreatitis in patients with gallstones and the effect of cholecystectomy on this risk have been unknown. The complete medical records of the 2,583 residents of Rochester, Minnesota, who had gallstones diagnosed between 1950 and 1970 were carefully reviewed to detect the development of acute pancreatitis. Acute pancreatitis developed in only 89 subjects (3.4% of the cohort); however, the relative risk for acute pancreatitis (before cholecystectomy) was increased 14 to 35 times in men and 12 to 25 times in women. The overall age- and sex-adjusted incidence of acute pancreatitis of the members of the cohort before cholecystectomy was 6.3 to 14.8 per 1,000 person-years of follow-up. Cholecystectomy in 1,560 patients without a prior attack of pancreatitis reduced the relative risk to 1.9 and 2.0 for men and women respectively. Of 58 patients who had a cholecystectomy after an attack of acute pancreatitis and underwent follow-up for a median of 15 years postoperatively, only 2 had another attack of acute pancreatitis, and the cause of the pancreatitis was unrelated to gallstones in both. In summary, patients with gallstones have a considerably increased relative risk for acute pancreatitis and, regardless of whether prior attacks of pancreatitis have occurred, cholecystectomy reduces this risk to almost the same level as in the general population. Because the overall incidence of pancreatitis is low, however, performance of cholecystectomy to prevent pancreatitis is indicated only if an attack of acute pancreatitis has already occurred.

Risk of Development of Gastric Carcinoma in Patients With Pernicious Anemia: A Population-Based Study in Rochester, Minnesota

To determine the long-term risk of the development of gastric cancer among patients with pernicious anemia, we identified the 152 residents of Rochester, Minnesota, who had well-documented pernicious anemia during the 30-year period 1950 through 1979. These patients were subsequently followed up for more than 1,550 person-years of observation. The observed risk of the development of a gastric cancer in this cohort was compared with that expected on the basis of incidence rates of gastric cancer for the local population. We found one case of gastric carcinoma among our 152 patients with pernicious anemia as compared with an expected incidence of 1.02 (relative risk, 1.0; 95% confidence interval, 0.02 through 5.5). We conclude that no strong indication exists for either radiographic or endoscopic surveillance in asymptomatic patients with pernicious anemia.

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.

Body composition during childhood and adolescence: relations to bone strength and microstructure

CONTEXT Numerous studies have examined the association of body composition with bone development in children and adolescents, but none have used micro-finite element (μFE) analysis of high-resolution peripheral quantitative computed tomography images to assess bone strength. OBJECTIVE This study sought to examine the relations of appendicular lean mass (ALM) and total body fat mass (TBFM) to bone strength (failure load) at the distal radius and tibia. DESIGN, PARTICIPANTS, AND SETTING This was a cross-sectional study of 198 healthy 8- to <15-year-old boys (n = 109) and girls (n = 89) performed in a Clinical Research Unit. RESULTS After adjusting for bone age, height, fracture history, ALM, and TBFM, multiple linear regression analyses in boys and girls, separately, showed robust positive associations between ALM and failure loads at both the distal radius (boys: β = 0.92, P < .001; girls: β = 0.66, P = .001) and tibia (boys: β = 0.96, P < .001; girls: β = 0.66, P < .001). By contrast, in both boys and girls the relationship between TBFM and failure load at the distal radius was virtually nonexistent (boys: β = -0.07; P = .284; girls: β = -0.03; P = .729). At the distal tibia, positive, albeit weak, associations were observed between TBFM and failure load in both boys (β = 0.09, P = .075) and girls (β = 0.17, P = .033). CONCLUSIONS Our data highlight the importance of lean mass for optimizing bone strength during growth, and suggest that fat mass may have differential relations to bone strength at weight-bearing vs non-weight-bearing sites in children and adolescents. These observations suggest that the strength of the distal radius does not commensurately increase with excess gains in adiposity during growth, which may result in a mismatch between bone strength and the load experienced by the distal forearm during a fall. These findings may explain, in part, why obese children are over-represented among distal forearm fracture cases.

Effects of Referral Bias on Surgical Outcomes: A Population-Based Study of Surgical Patients 90 Years of Age or Older

During the 11-year period 1975 through 1985, 1,063 surgical procedures were performed on 795 Mayo Clinic patients 90 years of age or older. Preoperative conditions, surgical setting, and perioperative morbidity and mortality were analyzed in a comparison of the local residents of Olmsted County, Minnesota (N = 224), with patients from outside the county but within 250 miles (N = 456) or referrals from a distance of 250 miles or further (N = 115). In comparison with non-Olmsted County patients, Olmsted County patients were generally older, had more preoperative chronic diseases, and underwent more emergency operations. Patients who had traveled 250 miles or more to the Mayo Clinic were more likely to be men and referred for cancer-related surgical procedures. The risks of major morbidity and mortality within 48 hours postoperatively were increased in patients with more preoperative chronic diseases and those undergoing emergency procedures, characteristics most common in Olmsted County patients. Because of differences in these factors between groups, perioperative risks averaged over our entire patient series underestimated risks that would be expected from a population-based cohort such as Olmsted County residents. In general, data from tertiary medical centers probably do not accurately reflect overall practice or outcomes in community settings.

Decline in Bilateral Orchiectomy for Prostate Cancer in Olmsted County, Minnesota, 1956–2000

OBJECTIVE To assess long-term secular trends in the utilization of bilateral compared with unilateral orchiectomy in the community. PATIENTS AND METHODS This population-based descriptive study reviewed medical records of all Olmsted County, Minnesota, men undergoing orchiectomy between 1956 and 2000. RESULTS Over the 45-year study period, 381 Olmsted County men had a first unilateral orchiectomy, while 431 underwent bilateral orchiectomy (including 8 with a second unilateral orchiectomy). There was no change over time in the age-adjusted utilization of unilateral orchiectomy, which was performed for a wide range of indications, mostly cryptorchidism and testicular malignancy. Most bilateral procedures, on the other hand, were in elderly men for castration, and trends over time generally paralleled those reported for prostate cancer in this community. CONCLUSION The declining incidence of prostate cancer in recent years, combined with a shift to earlier stages and younger ages at diagnosis, and the development of pharmacological approaches to hormonal manipulation have led to a dramatic decline in the utilization of bilateral orchiectomy, while unilateral orchiectomy rates have remained unchanged.