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Patrick S Parfrey

Publications and source records attributed to Patrick S Parfrey.

25 records · Page 2Linked to original sources
PubMed2002

Clinical and genetic epidemiology of inherited renal disease in Newfoundland.

Clinical and genetic epidemiology of inherited renal disease in Newfoundland. Newfoundland's geography, settlement, and socioeconomic development have produced a population useful for the study of genetic diseases. This review examines the clinical and genetic epidemiologic studies of inherited renal diseases undertaken in this population in the past 15 years. Common founder effects and large families through each generation provided very extensive pedigrees with autosomal-dominant diseases, such as polycystic kidney disease (PKD) and von Hippel-Lindau disease. In the former disease the diagnostic utility of renal ultrasound was determined, as was the prognostic impact of genotype, the role of the renin-angiotensin system in the pre-hypertensive phase, the potential for somatic mutations of the PKD2 gene, or the combination of mutations in the PKD1 and PKD2 genes, in single cells to induce cysts, and the demonstration that human transheterozygotes of PKD1 and -2 are not embryonically lethal. The presence of multiple genetic isolates and the high coefficient of kinship have predisposed to autosomal recessive diseases such as Bardet-Biedl syndrome (BBS), autosomal-recessive PKD, primary hyperoxaluria, and dihydroxyadenine urolithiasis. We have reported the clinical manifestations and natural history of the BBS, with particular emphasis on the fact that renal abnormalities are cardinal manifestations of the disease, the presence of at least six different genotypes, the identity and function of the BBS6 gene, and the presence of three different BBS6 mutations. Because of its relatively homogenous origins and high coefficient of kinship, Newfoundland's population also may be useful for the study of complex diseases such as preeclampsia. Using unbiased ascertainment and strict diagnostic criteria, we have found a significant risk of preeclampsia and non-proteinuric gestational hypertension in sisters of probands with preeclampsia, particularly when probands are defined by severity of preeclampsia, an observation that supports a study to search for susceptibility genes. We conclude that collaborations between clinical epidemiologists and molecular geneticists, using the Newfoundland population, have provided important clinical and mechanistic insights into inherited renal diseases.

Bardet-Biedl Syndrome↗
PubMed2002

Familial risk of preeclampsia in Newfoundland: a population-based study.

This study sought to quantify the familial risk of preeclampsia (proteinuric hypertension) in Newfoundland and to identify characteristics in probands that predict increased familial risk. Reviewed were 5173 obstetric charts from 10 hospitals, representing 99% of deliveries on the island of Newfoundland for a 1-yr period from April 1996 to March 1997; pregnancy-induced hypertension was diagnosed according to strict criteria. Family obstetric histories were obtained from identified probands with preeclampsia, and sisters and mothers of probands were interviewed. In addition, the obstetric charts from sisters and mothers were reviewed to identify preeclampsia. The incidence of preeclampsia in the population was 5.6% (n = 292), and in primiparous women it was 7.9%. Factors independently associated with increased risk of preeclampsia included primiparous delivery, multiple gestation, pregestational and gestational diabetes, maternal age of more than 35 yr, and region of the province. Of 330 sisters identified, 217 had 445 pregnancies, with 331 charts located for review. The incidence of preeclampsia (based on chart review) in 163 primiparous sisters was 20.2%. The relative risk of preeclampsia in primiparous sisters of probands with preeclampsia compared with primiparous women in the population was 2.6 (95% confidence interval, 1.8 to 3.6). Factors in probands independently associated with a higher risk of preeclampsia in sisters included at least 2+ proteinuria and region of the province. This population-based study, which used unbiased ascertainment and strict diagnostic criteria, demonstrated a significantly higher risk of preeclampsia in sisters of probands with preeclampsia, particularly when probands were defined by severity of preeclampsia and by geographic region.

Adult↗
PubMed2000

Serial change in echocardiographic parameters and cardiac failure in end-stage renal disease.

Echocardiographic abnormalities are the rule in patients starting dialysis therapy and are associated with the development of cardiac failure and death. It is unknown, however, whether regression of these abnormalities is associated with an improvement in prognosis. As part of a prospective cohort study with mean follow-up of 41 mo, 227 patients had echocardiography at inception and after 1 yr of dialysis therapy. Improvements in left ventricular (LV) mass index, volume index, and fractional shortening were seen in 48, 48, and 46%, respectively. Ninety patients had developed cardiac failure by 1 yr of dialysis therapy. Twenty-six percent of the remaining 137 patients subsequently developed new-onset cardiac failure. The mean changes in LV mass index were 17 g/m(2) in those who subsequently developed cardiac failure compared with 0 g/m(2) among those who did not (P = 0.05). The corresponding values were -8 versus 0% for fractional shortening (P < 0.0001). The associations between serial change in both LV mass index and fractional shortening and subsequent cardiac failure persisted after adjusting for baseline age, diabetes, ischemic heart disease, and the corresponding baseline echocardiographic parameter. Regression of LV abnormalities is associated with an improved cardiac outcome in dialysis patients. Serial echocardiography adds prognostic information to one performed at baseline.

Analysis of Variance↗