Til Stürmer

Obesity, overweight and patterns of osteoarthritis: the Ulm Osteoarthritis Study

The objective of this study was to assess the association between obesity and osteoarthritis (OA) of the knee, hip, and hand. OA patterns were studied in 809 patients with knee or hip joint replacement due to OA. Patients with OA were categorized as having bilateral or generalized OA according to the presence of radiographic OA in the contralateral joint or different finger joints, and as normal weight, overweight, or obese according to their body mass index (BMI). Odds ratios (OR) and 95% confidence intervals (CI) for relative weight and OA patterns were estimated with multivariable logistic regression. Eighty-five percent of participants had bilateral OA, 26% had generalized OA, and 31% were obese. Obesity (BMI >/= 30 kg/m(2); OR = 8.1; 95% CI: 2.4-28) and overweight (BMI >/= 25 kg/m(2); OR = 5.9; 95% CI: 2.0-18) were strongly associated with bilateral knee OA. No association between obesity and bilateral hip OA (OR = 0.7; 95% CI: 0.3-1.7) nor generalized OA (OR = 1.1; 95% CI: 0.6-2.1) was observed. Obesity seems to be a mechanical rather than a systemic risk factor for OA with the knee joint being especially susceptible.

Individual and joint contribution of family history and Helicobacter pylori infection to the risk of gastric carcinoma

Helicobacter pylori infection and a positive family history of gastric carcinoma have been identified as risk factors for the disease. It is unclear, however, to what degree their impact on the risk of gastric carcinoma is independent, because H. pylori also clusters within families.

Prevalence of generalised osteoarthritis in patients with advanced hip and knee osteoarthritis: The Ulm Osteoarthritis Study

OBJECTIVES Different prevalences of generalised osteoarthritis (GOA) in patients with knee and hip OA have been reported. The aim of this investigation was to evaluate radiographic and clinical patterns of disease in a hospital based population of patient subgroups with advanced hip and knee OA and to compare the prevalence of GOA in patients with hip or knee OA, taking potential confounding factors into account. METHODS 420 patients with hip OA and 389 patients with knee OA scheduled for unilateral total joint replacement in four hospitals underwent radiographic analysis of ipsilateral and contralateral hip or knee joint and both hands in addition to a standardised interview and clinical examination. According to the severity of radiographic changes in the contralateral joints (using Kellgren-Lawrence ⩾ grade 2 as case definition) participants were classified as having either unilateral or bilateral OA. If radiographic changes of two joint groups of the hands (first carpometacarpal joint and proximal/distal interphalangeal joints defined as two separate joint groups) were present, patients were categorised as having GOA. RESULTS Patients with hip OA were younger (mean age 60.4 years) and less likely to be female (52.4%) than patients with knee OA (66.3 years and 72.5% respectively). Intensity of pain and functional impairment at hospital admission was similar in both groups, while patients with knee OA had a longer symptom duration (median 10 years) compared with patients with hip OA (5 years). In 41.7% of patients with hip OA and 33.4% of patients with knee OA an underlying pathological condition could be observed in the replaced joint, which allowed a classification as secondary OA. Some 82.1% of patients with hip and 87.4% of patients with knee OA had radiographic changes in their contralateral joints (bilateral disease). The prevalence of GOA increased with age and was higher in female patients. GOA was observed more often in patients with knee OA than in patients with hip OA (34.9% versus 19.3%; OR=2.24; 95% CI: 1.56, 3.21). Adjustment for the different age and sex distribution in both patient groups, however, takes away most of the difference (OR=1.32; 95% CI: 0.89, 1.96). CONCLUSION The crude results confirm previous reports as well as the clinical impression of GOA being more prevalent in patients with advanced knee OA than in patients with advanced hip OA. However, these different patterns might be attributed to a large part to a different distribution of age and sex in these hospital based populations.

Reliability and validity of clinical outcome measurements of osteoarthritis of the hip and knee--a review of the literature.

SummaryHigh reliability and validity of clinical rating schemes is crucial for their use as outcome measurements of treatment of hip and knee osteoarthritis. In this paper, we review the empirical evidence on the reliability and validity of commonly used clinical scores. Clinical scores and related reliability and validity studies were identified by systematic literature search. Scores were classified according to the type and joint. Reliability and validity studies were characterized according to design, population, number and qualification of observers, number of measurements, time interval between repeat measurements and results. Reliability and validity studies were reported for only 6 and 15 of the 45 identified clinical scores, respectively. Although comparisons are difficult due to differences in study design, relatively high reliability was reported for most measurements of pain, stiffness, and physical function, while results are less conclusive for clinical signs. Most validity studies focused on the correlation between various scores. Correlation was generally found to be high for overall numerical ratings, but scores often differed with respect to the interpretation of these ratings. Validity has been more comprehensively studied for Lequesnes scores, WOMAC, and ILAS, and these scores have shown satisfactory responsiveness to different treatment effects. Overall, knowledge on reliability and validity of clinical scores of hip and knee osteoarthritis is limited, underlining the need for further properly designed and conducted studies.

Provider Delay Among Patients With Breast Cancer in Germany: A Population-Based Study

PURPOSE Delaying the diagnosis and initiation of treatment of cancer is likely to result in tumor progression and a worse prognosis. We examined sources and consequences of provider delay among female breast cancer patients in a population-based study in Germany. PATIENTS AND METHODS Three hundred eighty women, who were ages 18 to 80 years and who had invasive breast cancer, were interviewed with respect to the diagnostic process. Provider delay was defined as time from first presentation to a health care provider until initiation of cancer treatment. RESULTS Median provider delay was 15 days and did not substantially differ by the specialty of first consulted physician. Delays in the diagnostic work-up were mainly because of erroneous initial suspicion of a benign breast disease or because of time constraints by patients or physicians. Provider delay over 3 months was found in 11% of all breast cancer cases and was associated with patient characteristics such as higher education (odds ratio [OR] = 2.6; 95% confidence interval [CI], 1.3 to 5.4), full-time employment (OR = 2.5; 95% CI, 1.1 to 5.5), family history of breast cancer (OR = 2.8; 95% CI, 1.2 to 6.2), and presenting with a non-breast symptom (OR = 4.3; 95% CI, 1.7 to 10.9). The association between duration of diagnostic work-up and stage at diagnosis was U shaped, with the highest proportions of metastasized breast cancer tumors among women with very short (< 7 days) or very long (> 3 months) duration. CONCLUSION Diagnostic work-up is within reasonably short time limits among most patients with breast cancer in Germany. Although the association between delay and tumor stage seems to be complex, any delay in diagnostic work-up should be kept to a minimum.

Socio-demographic factors, health behavior and late-stage diagnosis of breast cancer in Germany: A population-based study

Late-stage diagnosis of breast cancer is associated with poor survival. Identification of individuals at high risk of late-stage diagnosis could be an effective step to reduce breast cancer mortality. We examined the association of socio-demographic factors and health behavior with breast cancer stage in a population-based sample of 380 female breast cancer patients in Saarland, Germany. Overall, 182 women (47.9%) were diagnosed with late-stage (regional or distant) breast cancer. After control for potential confounding by multivariate logistic regression, an increased risk of late-stage diagnosis was observed for older age (OR = 1.8; 95% CI 1.0-3.2), foreign nationality (OR = 3.9; 95% CI 0.7-20.8), living in large households (OR = 1.7; 95% CI 1.0-2.9), non-participation in general health check-up (OR = 1.5; 95% CI 0.9-2.4) and low interest in health care (OR = 1.6; 95% CI 1.0-2.7). The proportion of late-stage cancer was clearly decreased when tumors were detected by screening (OR = 0.4; 95% CI 0.2-0.8). Certain socio-demographic factors and characteristics of health behavior seem to represent independent risk indicators of late-stage diagnosis.

Hormone replacement therapy and patterns of osteoarthritis: baseline data from the Ulm Osteoarthritis Study

OBJECTIVES It has been suggested that hormone replacement therapy (HRT) may protect against osteoarthritis (OA). The aim of this paper was to assess the association between HRT and radiographically defined patterns of OA. METHODS 475 consecutive women aged 50 years or older (mean age 66.1) who underwent hip or knee joint replacement because of advanced OA in four hospitals in south west Germany were enrolled in a cross sectional study. Participants underwent a standardised interview including detailed history of medication use and a physical examination. Furthermore, radiographs of the joint being replaced and of the contralateral joint as well as of both hands were obtained. Patients were categorised as having bilateral or unilateral OA according to the presence or absence of radiographic OA in the contralateral joint. If radiographic OA of different hand and finger joint groups was present, participants were categorised as having generalised OA (GOA). Logistic regression was used to estimate odds ratios and their 95% confidence intervals for the association between HRT and bilateral or GOA while adjusting for potential confounders. RESULTS Fifty five women (11.6%) were using HRT. The median duration of use was 5.4 years. The prevalence of bilateral and GOA was similar among users of ORT (86.3% and 27.5%, respectively) and among non-users of HRT (88.7% and 35.7%, respectively). After adjustment for potential confounding factors, the odds ratios (95% confidence intervals) of bilateral OA and GOA among HRT users compared with non-users was 1.21 (0.48, 3.03) and 1.21 (0.53, 2.74), respectively. CONCLUSION Despite limited generalisability because of the selective study sample, these data do not support the hypothesis that HRT acts as a systemic protective factor against OA.

Assessing the prevalence of hand osteoarthritis in epidemiological studies. The reliability of a radiological hand scale

OBJECTIVE The hands are often involved in the osteoarthritic disease process. A radiological grading scale is presented, derived from a published atlas, to assess the prevalence of hand osteoarthritis (OA) involvement in clinical and epidemiological studies and its reproducibility is studied. METHODS This hand scale is based on the radiological feature “joint space narrowing”, which represents the macromorphological process of cartilage loss. Osteophytes and sclerosis are less important unless seen in conjuction with joint space narrowing. Nine individual joints per hand (four proximal interphalangeal joints (PIP), four distal interphalangeal joints (DIP), first carpometacarpal joint (CMC-1)) are scored dichotomously for the presence of OA. To save time and to increase reliability a severity grading of radiological features is not performed. To determine inter-rater and intra-rater reliability of the individual joints and the presence of OA in two separate joint groups (⩾ 2 PIP or DIP and at least one CMC-1, used to define “generalised OA” in the ongoing Ulm Osteoarthritis Study) 50 pairs of anteroposterior hand radiographs were read by two investigators twice within one month. The κ coefficient was calculated to quantify the strength of associations. RESULTS On average five minutes were needed to score one hand radiograph. Both raters were able to reproduce their own readings in all individual joints and for the presence of OA in two separate joint groups after one month. Reliability was highest for the PIP joints (κ: 0.56–1.00) it was slightly lower for the DIP joints (0.38–0.87), for the CMC-1 joints (0.58–0.69) and for OA in two separate joint groups (0.54). The values for inter-rater agreement were good as well, κ coefficients ranged from 0.52 to 0.92. CONCLUSION This grading scale was shown to be reliable within and between readers for all the individual joints as well as for the presence of OA in two separate joint groups. Scoring a limited number of joints dichotomously makes this scale efficient and therefore useful for clinical and epidemiological trials, when dealing with large patient samples.

Potential gain in efficiency and power to detect gene-environment interactions by matching in case-control studies

Background: There is growing interest in interactions between genetic and environmental risk factors of disease, but adequate power to detect such interactions in epidemiologic studies is of concern. The aim of this paper is to quantify the effect of matching on the efficiency of estimation and power to detect gene‐environment interactions in case‐control studies. Methods: Starting from an empirical example in cancer epidemiology, we simulated frequency matched and unmatched case‐control studies for a wide range of assumptions regarding the prevalence and the effects of an environmental and a genetic factor on disease risk as well as the quality and quantity of the interaction between these factors. Simulated studies were analyzed with multivariable logistic regression. Results: Matching increased the efficiency and power in most scenarios. The gain was most pronounced in scenarios assuming a low prevalence of the environmental exposure. In such scenarios, equivalent power was only obtained with more than twice as many unmatched than matched controls. Conclusions: Frequency matching for known environmental risk factors with a low prevalence in the population may increase the efficiency of estimation and power of case‐control studies to detect gene‐environment interactions considerably. Investigators should weigh the gain in efficiency and power against known potential disadvantages of matching. Genet. Epidemiol. 18:63–80, 2000.

First carpometacarpal and interphalangeal osteoarthritis of the hand in patients with advanced hip or knee OA. Are there differences in the aetiology

Differences in the aetiology of osteoarthritis (OA) of the first carpometacarpal joints (CMC-1) and the interphalangeal joints (IP) have been reported. It was the purpose of this investigation to evaluate whether isolated OA of the first carpometacarpal joints and the interphalangeal joints differs in its aetiology, considering potential risk factors such as age, gender, body mass index, occupational history, OA in the hip or knee joints, hypertension and diabetes in patients with advanced hip or knee OA. Included in this investigation were 639 patients scheduled for either hip or knee replacement because of advanced OA. As well as a standardised interview and clinical examination, bilateral radiographs of both hands were obtained. According to the presence or absence of radiographic OA, participants were categorised as having CMC-1 OA (= 1 joint) or IP OA (= 2 joints), either isolated or in combination. Odds ratios (OR) and their 95% confidence intervals (CI) for potential determinants of OA were estimated using multivariable logistic regression.Of the total number of patients, 184 had CMC-1 OA and 424 IP OA. Patients with CMC-1 OA were more likely to be female (77.2%), and to have knee OA (62.5%) and hypertension (63.0%), than patients without CMC-1 OA. No differences between CMC-1 OA and IP OA were observed for the role of age, body mass index and diabetes. Age was associated with both CMC and IP OA. Female gender was independently associated with CMC-1 OA (OR=1.79; 95% CI: 1.16–2.74) but not with IP OA. Our data suggest a possible impact of age and female gender on the aetiology of CMC-1 OA and of age on IP-OA, at least in patients with advanced hip or knee OA.