John A. Baron

Incidence rates of dislocation, pulmonary embolism, and deep infection during the first six months after elective total hip replacement.

Background: The lengths of acute hospital stays following total hip replacement have diminished substantially in recent years. As a result, a greater proportion of complications occurs following discharge. Data on the incidence trends of major complications of total hip replacement would facilitate recognition and management of these adverse events.Methods: We used Medicare claims data on beneficiaries sixty-five years and older who had had elective, primary total hip replacement for a reason other than a fracture (58,521 patients) or had had revision total hip replacement (12,956 patients) between July 1, 1995, and June 30, 1996. We calculated incidence rates of dislocation, pulmonary embolism, and deep hip infection per 10,000 person-weeks for four time-periods following the admission for the surgery (during the index hospitalization, from discharge to four weeks postoperatively, from five to thirteen weeks postoperatively, and from fourteen to twenty-six weeks postoperatively). We then used life-table methods to estimate the cumulative incidence of each complication over the first six postoperative months.Results: Of the patients who had had a primary total hip replacement, 3.9% had a dislocation, 0.9% had a pulmonary embolism, and 0.2% had a deep infection in the first twenty-six postoperative weeks. In the revision total hip replacement cohort, the proportions with dislocation, pulmonary embolism, and deep infection were 14.4%, 0.8%, and 1.1%, respectively. The rates of these adverse outcomes were highest during the index hospitalization, diminished considerably in the period from discharge to four weeks postoperatively, and continued to drop in the periods from five to thirteen and fourteen to twenty-six weeks postoperatively.Conclusions: The incidence rates of dislocation, pulmonary embolism, and deep infection are highest immediately after total hip replacement, but they continue to be elevated throughout the first three postoperative months. With the lengths of hospital stays continuing to diminish, an increasing proportion of complications will occur in outpatients. These findings provide a basis for developing strategies to prevent these complications in the postdischarge management of patients who have had elective total hip replacement.Level of Evidence: Prognostic study, Level II-1 (retrospective study). See p. 2 for complete description of levels of evidence.

Genital talc exposure and risk of ovarian cancer

Epidemiologic studies have suggested an increased risk for ovarian cancer associated with the use of talcum powder in genital hygiene, but the biologic credibility of the association has been questioned. We conducted a population‐based case‐control study in eastern Massachusetts and New Hampshire involving 563 women with newly diagnosed epithelial ovarian cancer and 523 control women selected either by random digit dialing or through lists of residents. Use of body powders was assessed through personal interview and the exposure odds ratio (OR) for the use of talc in genital hygiene was calculated. Cases were more likely than controls (45% vs. 36%) to have used talc as a body powder in some manner, and the excess was confined to patients who used talc on the perineum directly or as a dusting powder to underwear or sanitary napkins. Relative to women who never used body powder or used it only in non‐genital areas, the OR (and 95% confidence interval) associated with genital exposure to talc was 1.60 (1.18 and 2.15) after adjustment for age, study location, parity, oral contraceptive use, body mass index and family history of breast or ovarian cancer. Exposure prior to rather than after a first livebirth appeared to be more harmful, and the association was most apparent for women with invasive serous cancers and least apparent for those with mucinous tumors. We conclude that there is a significant association between the use of talc in genital hygiene and risk of epithelial ovarian cancer that, when viewed in perspective of published data on this association, warrants more formal public health warnings. Int. J. Cancer 81:351–356, 1999.

Chromoendoscopy detects more adenomas than colonoscopy using intensive inspection without dye spraying.

Conventional colonoscopy misses some neoplastic lesions. We compared the sensitivity of chromoendoscopy and colonoscopy with intensive inspection for detecting adenomatous polyps missed by conventional colonoscopy. Fifty subjects with a history of colorectal cancer or adenomas underwent tandem colonoscopies at one of five centers of the Great Lakes New England Clinical Epidemiology and Validation Center of the Early Detection Research Network. The first exam was a conventional colonoscopy with removal of all visualized polyps. The second exam was randomly assigned as either pan-colonic indigocarmine chromoendoscopy or standard colonoscopy with intensive inspection lasting >20 minutes. Size, histology, and numbers of polyps detected on each exam were recorded. Twenty-seven subjects were randomized to a second exam with chromoendoscopy and 23 underwent intensive inspection. Forty adenomas were identified on the first standard colonoscopies. The second colonoscopies detected 24 additional adenomas: 19 were found using chromoendoscopy and 5 were found using intensive inspection. Chromoendoscopy found additional adenomas in more subjects than did intensive inspection (44% versus 17%) and identified significantly more missed adenomas per subject (0.7 versus 0.2, P < 0.01). Adenomas detected with chromoendoscopy were significantly smaller (mean size 2.66 ± 0.97 mm) and were more often right-sided. Chromoendoscopy was associated with more normal tissue biopsies and longer procedure times than intensive inspection. After controlling for procedure time, chromoendoscopy detected more adenomas and hyperplastic polyps compared with colonoscopy using intensive inspection alone. Chromoendoscopy detected more polyps missed by standard colonoscopy than did intensive inspection. The clinical significance of these small missed lesions warrants further study.