Neighbourhood factors and tuberculosis incidence in Cape Town: A negative binomial regression and spatial analysis.

OBJECTIVES: Although the link between poverty and tuberculosis (TB) is widely recognised, limited studies have investigated the association between neighbourhood factors and TB incidence. Since the factors influencing different episodes of TB might be different, this study focused on the first episode of TB disease (first-episode TB). METHODS: All first episodes in previously linked and geocoded TB notification data from 2007 to 2015 in Cape Town, South Africa, were aggregated at the neighbourhood level and merged with the 2011 census data. We conducted an ecological study to assess the association between neighbourhood incidence of first-episode TB and neighbourhood factors (total TB burden [all episodes] in the previous year, socioeconomic index, mean household size, mean age, and percentage males) using a negative binomial regression. We also examined the presence of hotspots in neighbourhood TB incidence with the Global Moran's I statistic and assessed spatial dependency in the association between neighbourhood factors and TB incidence using a spatial lag model. RESULTS: The study included 684 neighbourhoods with a median first-episode TB incidence rate of 114 (IQR: 0-345) per 100,000 people. We found lower neighbourhood socioeconomic index (SEI), higher neighbourhood total TB burden, lower neighbourhood mean household size, and lower neighbourhood mean age were associated with increased neighbourhood first-episode TB incidence. Our findings revealed a hotspot of first-episode TB incidence in Cape Town and evidence of spatial dependency in the association between neighbourhood factors and TB incidence. CONCLUSION: Neighbourhood TB burden and SEI were associated with first-episode TB incidence, and there was spatial dependency in this association. Our findings can inform targeted interventions to reduce TB in high-risk neighbourhoods, thereby reducing health disparities and promoting health equity.

A study of a new osmotic purgative for colonoscopy. Is Golytely worth its salt?

An osmotic laxative containing polyethylene glycol and sodium sulfate (Golytely Braintree Laboratories, Inc., Braintree, MA) is widely used to clean the colon for colonoscopy. However, its salty taste makes the mixture unpalatable. We therefore tested the claim that a similar solution but without sodium sulfate (Golytely-RSS Braintree Laboratories, Inc., Braintree, MA) makes preparation of the colon more acceptable to patients in a double-blinded randomized controlled trial. Colonic preparation using polyethylene glycol with or without sodium sulfate was randomized in 100 patients due to undergo colonoscopy. The overall acceptability of the regimen was measured on a linear analogue scale and an estimate of symptoms was obtained. Body weight and serum electrolytes, urea, creatinine, hemoglobin and hematocrit were determined before and after preparation in order to assess fluid absorption. The efficacy of colonic cleansing was graded by the colonoscopist. Four patients did not complete the protocol, 47 received the regimen containing sodium sulfate and 49 received the regimen without it. The two groups did not differ in age or body mass. There was no statistical difference in the overall acceptability of the two regimens to the patients (median acceptability rating 74 for regimen with sodium sulfate, range 4-100 compared with 77 for regimen without, range 3-100, p = 0.32, Mann-Whitney test). Nor was there any difference in taste, nausea, vomiting, cramping or perianal discomfort or in the endoscopists' rating of the cleanliness of the colon. The serum sodium concentration rose slightly (mean 1.6 mmol/L) when the regimen with sodium sulfate was used.(ABSTRACT TRUNCATED AT 250 WORDS)