OBJECTIVETo investigate the relationship between silica or silicosis and lung cancer in a large cohort of silicotic workers in Hong Kong.

METHODSAll workers with silicosis in Hong Kong diagnosed between 1981 and 1998 were followed up till the end of 1999 to ascertain their vital status and causes of death, using the corresponding mortality rates of Hong Kong males of the same period as external comparison. Standardized mortality ratios (SMR) for lung cancer and other major causes of death were calculated. Person-year method was used. Axelson's indirect method was performed to adjust for the confounding effect of smoking. Penalized smoothing spline (p-spline) models were used to evaluate the exposure-response relationship between silica dust exposure and lung cancer mortality.

RESULTSA total of 2789 newly diagnosed cases of silicosis were included in the cohort, with an overall 24 992.6 person-years of observations. The loss-to-follow-up rate was only 2.9%. Surface construction workers (51%) and underground caisson workers (37%) constituted the major part of the cohort. There were 853 silicotics observed with an average age at death of 63.8 years. The SMR for all causes and all cancers increased significantly. The leading cause of death was non-malignant respiratory diseases. About 86 deaths were from lung cancer, giving a SMR of 1.69 (95% CI: 1.35 approximately 2.09). The risk of lung cancer death among workers in surface construction, underground caisson, and entire cohort was reduced to 1.12 (95% CI: 0.89 approximately 1.38), 1.09 (95% CI: 0.82 approximately 1.42) and 1.56 (95% CI: 0.98 approximately 2.36) respectively, after indirectly adjusting for smoking.

RESULTSfrom P-spline model did not show a clear exposure-response relationship between silica dust (CDE and MDC) and lung cancer mortality.

CONCLUSIONThis cohort study did not show an increased risk of lung cancer mortality among silicotic workers. P-spline model does not support an exposure-response relationship between silica dust exposure and lung cancer mortality.

Adult ; Aged ; Dust ; Follow-Up Studies ; Hong Kong ; epidemiology ; Humans ; Lung Neoplasms ; etiology ; mortality ; Male ; Middle Aged ; Occupational Exposure ; adverse effects ; Retrospective Studies ; Silicosis ; complications ; mortality

BACKGROUNDPrimary open-angle glaucoma (POAG) is characterized by optic nerve damage and consists of a group of genetically heterogeneous disorders. This study was to investigate the associations of genetic and environmental factors with POAG in a hospital-based Chinese population.

METHODSThirty-two adult onset POAG patients and 96 age-sex matched control subjects were studied by multivariable logistic regression analysis for the relationships between POAG and its risk factors including family history, diabetes, hypertension, cardiovascular diseases, cigarette smoking, alcohol consumption and polymorphisms of the myocilin and the optineurin genes.

RESULTSUnivariate analysis showed that POAG was related to family history, cardiovascular disease, alcohol consumption and a myocilin sequence alteration (T353I) (P < 0.04). Multivariable logistic regression analysis confirmed that POAG was significantly associated with family history (OR = 20.2), hypertension (OR = 3.58), cigarette smoking (OR = 10.8), alcohol consumption (OR = 0.028) and T353I (OR = 6.03, all P < 0.05).

CONCLUSIONSFamily history, hypertension, cigarette smoking and T353I in the myocilin gene are risk factors for POAG. Alcohol consumption, however, has a protective effect.

Adult ; Aged ; Aged, 80 and over ; Alcohol Drinking ; adverse effects ; Cytoskeletal Proteins ; Eye Proteins ; genetics ; Female ; Glaucoma, Open-Angle ; etiology ; genetics ; Glycoproteins ; genetics ; Humans ; Hypertension ; complications ; Logistic Models ; Male ; Middle Aged ; Risk Factors ; Smoking ; adverse effects

OBJECTIVETo detect single nucleotide polymorphisms (SNPs) of the myocilin (MYOC) gene and to investigate their associations with primary open-angle glaucoma (POAG).

METHODSOne hundred and fifty-seven sporadic patients with POAG and 155 unrelated control subjects without POAG were recruited from staff and visitors to the Prince of Wales Hospital between 1998 and 2000. All study subjects are ethnic Chinese living in Hong Kong. The two populations were matched in frequencies of gender and age. The SNPs of the MYOC gene in POAG patients and control subjects were screened and identified by high throughout conformation sensitive gel electrophoresis and fluorescent labeling automated sequencing. The genotype frequencies of each SNP in the two groups were compared by the Chi2 test or Fisher's exact 2-tailed test.

RESULTSA total of seventeen SNPs were identified from 2172 bp long of the MYOC gene, including all 3 exons and adjacent non-coding regions. The identified SNPs were 1-83G --> A, G12R, P16L, A17S, R46X, R76K, R91X, T123T, D208E, L215P, 730+35A --> G, A260A, I288I, E300K, T353I, Y471C and 1515+73G --> C, respectively. Of these, R91X, E300K and Y471C were found only in POAG patients. A significant difference between POAG patients and control subjects was found in the genotype frequencies of 1515+73G --> C. The frequency of the heterozygote (CG) was 0.6% in POAG patients, significantly less than the 4.5% in control subjects (Fisher's exact 2-tailed test, P=0.036, OR=0.136, 95%CI=0.022-0.828). No significant difference was found between the two populations in genotype frequencies of all other SNPs.

CONCLUSIONThe polymorphisms of the MYOC gene may be related to POAG.

Adult ; Aged ; Aged, 80 and over ; Amino Acid Substitution ; Base Sequence ; Case-Control Studies ; Cytoskeletal Proteins ; DNA ; chemistry ; genetics ; DNA Mutational Analysis ; Eye Proteins ; genetics ; Female ; Gene Frequency ; Genotype ; Glaucoma, Open-Angle ; genetics ; pathology ; Glycoproteins ; genetics ; Humans ; Male ; Middle Aged ; Point Mutation ; Polymorphism, Single Nucleotide

PURPOSE: The aims of this study were to investigate the prevalence of upper tract involvement in ketamine-associated uropathy, and to determine the predictors of hydronephrosis in patients with a history of ketamine abuse. METHODS: This was a cross-sectional study of a prospective cohort of patients with ketamine-associated uropathy. Data including demographics, pattern of ketamine abuse, pelvic pain and urgency or frequency (PUF) symptom score, uroflowmetry (UFM) parameters, serum renal function, and liver function tests were collected. Upon consultation, ultrasonography was performed to assess the function of the urinary system. RESULTS: From December 2011 to October 2015, we treated 572 patients with ketamine-associated uropathy. Of these patients, 207 (36.2%) had managed to achieve abstinence at the time of their first consultation. Ninety-six patients (16.8%) in the cohort were found to have hydronephrosis on ultrasonography. Univariate analysis identified age, duration of ketamine abuse, PUF symptom score, voided volume on UFM, serum creatinine levels >100 μmol/L, and an abnormal serum liver enzyme profile as factors associated with hydronephrosis. Logistic regression revealed the following parameters to be statistically related to hydronephrosis: age (adjusted odds ratio [OR], 1.090; 95% confidence interval [CI], 1.020–1.166; P=0.012), functional bladder capacity (adjusted OR, 0.997; 95% CI, 0.995–0.999; P=0.029), serum creatinine >100 μmol/L (adjusted OR, 3.107; 95% CI, 1.238–7.794; P=0.016, and an abnormal serum liver enzyme profile (adjusted OR, 1.967; 95% CI, 1.213–3.187; P=0.006). CONCLUSIONS: Ketamine-associated uropathy can involve the upper urinary tract. Patient demographics as well as investigations of UFM, renal function tests, and liver function tests may allow us to identify at-risk patients.
Cohort Studies ; Creatinine ; Cross-Sectional Studies ; Cystitis ; Demography ; Humans ; Hydronephrosis ; Ketamine ; Liver ; Liver Function Tests ; Logistic Models ; Lower Urinary Tract Symptoms ; Odds Ratio ; Pelvic Pain ; Prevalence ; Prospective Studies ; Ultrasonography ; Urinary Bladder ; Urinary Tract* ; Urination Disorders

It is largely unknown whether lower urinary tract symptoms (LUTS) or acute retention of urine (AROU) is linked to shorter life expectancy in men. We conducted a multicenter, retrospective database analysis of patients undergoing transurethral resection of prostate (TURP) to study their relationships. Multivariate Cox regression analysis and Kaplan-Meier analysis with stratification to age and indication of TURP were performed. We further performed an age- and sex-matched survival analysis with the general population using data from the Census and Statistics Department of the Hong Kong Special Administrative Region (Hong Kong, China). From January 2002 to December 2012, 3496 patients undergoing TURP were included in our study, with 1764 patients in the LUTS group and 1732 patients in the AROU group. Old age, ischemic heart disease, cerebrovascular accident, and AROU were risk factors of mortality. Patients aged <70 years (adjusted hazard ratio [HR]: 1.52, 95% confidence interval [CI]: 1.11-2.09, P = 0.010) and 70-80 years (adjusted HR: 1.39, 95% CI: 1.15-1.70, P = 0.001) in the AROU group had worse survival than those in the LUTS group, but such difference was not demonstrated in patients aged >80 years. Compared to the general population, younger patients in the LUTS group appeared to have better survival (<70 years, P = 0.091; 70-80 years, P = 0.011), but younger patients in the AROU group had worse survival (<70 years, P = 0.021; 70-80 years, P = 0.003). For patients aged >80 years, survival was similar with the general population in both the LUTS and AROU groups. In conclusion, AROU at young age was associated with mortality, while early detection and management of LUTS may improve survival.
Age Factors ; Aged ; Aged, 80 and over ; Databases, Factual ; Humans ; Kaplan-Meier Estimate ; Lower Urinary Tract Symptoms ; Male ; Middle Aged ; Prostate/surgery* ; Prostatic Hyperplasia/surgery* ; Retrospective Studies ; Risk Factors ; Survival Analysis ; Transurethral Resection of Prostate/methods* ; Urinary Retention/surgery*