Bis(phenylacetyl) disulfide

28736513

Background
A recent study found lower self-reported prevalence of tobacco smoking in a peri-urban area of Lima, Peru than previously reported in urban samples. These regions encompass substantial proportions of Peru’s population – ones at greater risk of disease due to reduced healthcare access – but have been less often studied. We validate low smoking prevalence with urine cotinine and characterize chronic disease and lung function outcomes between non-, occasional, and daily smokers.

Methods
Data are from the CRONICAS Cohort Study, a population-based longitudinal study in four low-resource Peruvian settings, which began in 2010. Of a baseline cohort of 2978 adults, we prospectively followed 2583 (87%) to determine prevalence of chronic illness.

Results
In a baseline sub-sample of 382 participants, median adjusted cotinine was 0.0 mcg/mg (IQR 0-0) for both self-reported non-smokers and occasional smokers compared to 172.3 mcg/mg (IQR 0-709.2) for daily smokers. Creatinine-adjusted cotinine validated daily smoking prevalence of 4.7% at a cutoff of 100 mcg/mg. Kappa statistic for daily smoking and creatinine- adjusted cotinine ≥100 mcg/mg was 0.65 (95% CI 0.47, 0.83), indicating substantial agreement. At baseline, we found 3.3% daily and 8.9% occasional smoking by self-report for the full cohort. Follow-up indicated little difference in chronic disease prevalence between groups. Daily smokers trended toward having a greater decline in FVC (−1%; 95% CI -2.9, 0.8) and FEV1 (−1.3%; 95% CI -3.2, 0.6) over 40 months when compared to non-smokers, whereas the decline in lung function for occasional smokers was similar compared to non-smokers (−0.2% FVC; 95% CI -1.5, 1.0) and (0% FEV1; 95% CI -1.3, 1.3).

Conclusions
Our data places Peru within a previously-described pattern of smoking found in much of Latin America, favoring occasional over daily smoking and low cigarette consumption. We determine that there are not significant differences between smoking groups concerning chronic disease outcomes. We favor distinguishing between daily and occasional smokers in order to accurately characterize these low-use populations.

Electronic supplementary material
The online version of this article (doi:10.1186/s12971-017-0137-8) contains supplementary material, which is available to authorized users.

Tobacco, Smoking, Cotinine, Epidemiology

Low cigarette smoking prevalence in peri-urban Peru: results from a population-based study of tobacco use by self-report and urine cotinine

Brooks W. Morgan, Kathryn M. Leifheit, Karina M. Romero, Robert H. Gilman, Antonio Bernabe-Ortiz, J. Jaime Miranda, Harold I. Feldman, John J. Lima, William Checkley, CRONICAS Cohort Study

2017;

31636301

Electrolytes have a crucial role in maintaining health and their serum levels are homeostatically maintained within a narrow range by multiple pathways involving the kidneys. Here we use metabolomics profiling (592 fasting serum metabolites) to identify molecular markers and pathways associated with serum electrolyte levels in two independent population-based cohorts. We included 1523 adults from TwinsUK not on blood pressure-lowering therapy and without renal impairment to look for metabolites associated with chloride, sodium, potassium and bicarbonate by running linear mixed models adjusting for covariates and multiple comparisons. For each electrolyte, we further performed pathway enrichment analysis (PAGE algorithm). Results were replicated in an independent cohort. Chloride, potassium, bicarbonate and sodium associated with 10, 58, 36 and 17 metabolites respectively (each P < 2.1 × 10−5), mainly lipids. Of all the electrolytes, serum potassium showed the most significant associations with individual fatty acid metabolites and specific enrichment of fatty acid pathways. In contrast, serum sodium and bicarbonate showed associations predominantly with amino-acid related species. In the first study to examine systematically associations between serum electrolytes and small circulating molecules, we identified novel metabolites and metabolic pathways associated with serum electrolyte levels. The role of these metabolic pathways on electrolyte homeostasis merits further studies. Subject terms: Biomarkers, Nephrology

Metabolomic profiling identifies novel associations with Electrolyte and Acid-Base Homeostatic patterns

Cristina Menni,corresponding author#1 Linsay McCallum,#2 Maik Pietzner,3,4 Jonas Zierer,1,5 Alisha Aman,2 Karsten Suhre,6 Robert P. Mohney,6 Massimo Mangino,1 Nele Friedrich,3 Tim D. Spector,1 and Sandosh Padmanabhancorresponding author2

2019;