Risk factors for choledocholithiasis in a south Indian population: a case-control study

Chemical and structural analysis of gallstones from the Indian subcontinent

Representative gallstones from north and southern parts of India were analyzed by a combination of physicochemical methods: X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), CHNS analysis, thermal analysis and Nuclear Magnetic Resonance (NMR) spectroscopy (¹H and ¹³C). The stones from north Indian were predominantly consisting of cholesterol monohydrate and anhydrous cholesterol which was confirmed by XRD analysis. FTIR spectroscopy confirmed the presence of cholesterol and calcium bilirubinate in the south Indian gallstones. EDX spectroscopy revealed the presence of carbon, nitrogen, oxygen, calcium, sulfur, sodium and magnesium and chloride in both south Indian and north Indian gallstones. FTIR and NMR spectroscopy confirmed the occurrence of cholesterol in north Indian gallstones. The respective colour of the north Indian and south Indian gallstones was yellowish and black. The morphology of the constituent crystals of the north Indian and south Indian gallstones were platy and globular respectively. The appreciable variation in colour, morphology and composition of south and north Indian gallstones may be due to different food habit and habitat.

Systematic review with meta-analysis: coffee consumption and the risk of gallstone disease

BACKGROUND

Epidemiologic evidence on coffee consumption reducing the risk of gallstone disease has been contradictory.

AIM

To perform a meta-analysis of observational studies, to investigate an association and dose-response of coffee consumption with gallstone disease.

METHODS

We used PubMed and EMBASE databases to identify all published studies before June 2015. A random-effects model was used to compute a pooled relative risk (RR) and corresponding 95% confidence intervals (CIs).

RESULTS

One case-control study and five prospective cohort studies (with seven cohorts) involving 227,749 participants and 11,477 gallstone disease cases were included. Coffee consumption was significantly associated with a reduced risk of gallstone disease (RR, 0.83; 95% CI, 0.76 to 0.89; I(2) = 35.9%), based on prospective studies; specifically, we observed an inverse relation in females, but not in males. The case-control study did not reveal any association between coffee and gallstone disease (OR, 0.99; 95% CI, 0.64 to 1.53). In a dose-response analysis, the RR of gallstone disease was 0.95 (95% CI, 0.91 to 1.00; P = 0.049) per 1 cup/day of coffee consumption. A significant nonlinear dose-response association was also identified (P for nonlinearity = 0.0106). For people who drank 2, 4 and 6 cups of coffee per day, the estimated RRs of gallstone disease were 0.89 (95% CI, 0.79 to 0.99), 0.81 (95% CI, 0.72 to 0.92) and 0.75 (95% CI, 0.64 to 0.88), respectively, compared with the lowest level drinkers.

CONCLUSION

This study suggests that coffee consumption is related to a significantly decreased risk of gallstone disease.