A population-based assessment of the familial component of chronic kidney disease mortality

Genetic Contribution to Nonsquamous, Non-Small Cell Lung Cancer in Nonsmokers

INTRODUCTION

Lung carcinogenesis is strongly influenced by environmental and heritable factors. The genetic contribution to the different histologic subtypes is unknown.

METHODS

A population-based computerized genealogy resource linked to a statewide cancer registry of lung cancer cases (N = 5408) was analyzed to evaluate the heritable contribution to lung cancer histologic subtype in smokers (n = 1751) and nonsmokers (n = 818). Statistical methods were used to test for significant excess relatedness of lung cancer cases.

RESULTS

Significant excess distant relatedness was observed for all lung cancer histologic subgroups analyzed except for the SCLC subset (p = 0.213). When histologic subsets of smokers and nonsmokers with lung cancer were considered, excess relatedness was observed only in nonsmokers with NSCLC (n = 653 [p = 0.026]) and, in particular, in those nonsmokers with the nonsquamous histologic subtype (n = 561 [p = 0.036]). A total of 61 pedigrees demonstrating a significant excess risk of nonsquamous lung cancer in nonsmokers were identified, and an excess of cases in females was observed among the individuals with these high-risk pedigrees.

CONCLUSIONS

This analysis supports a genetic predisposition to lung cancer carcinogenesis in nonsmokers with nonsquamous NSCLC.

End Stage Renal Disease Predicts Increased Risk of Death in First Degree Relatives in the Norwegian Population

BACKGROUND

Increased risk of end stage renal disease (ESRD) and death in Norwegian living kidney donors has been reported, most of the donors were related to the recipient. The present study investigates risk of death in first degree relatives of ESRD patients.

METHODS

The Norwegian Population Registry, The Norwegian Cause of Death Registry and the Norwegian Renal Registry were linked. All citizens born in Norway, alive in 1960 and with at least one registered first degree relative were included; individuals who died during the first year of life were excluded. A cohort-design was used, ESRD in a first degree relative was the main exposure variable and death and causes of death were the main outcome variables. Cox regression statistics were used to investigate mortality risks.

RESULTS

5 130 600 individuals were included, 27 508 had at least one first degree relative with ESRD. 828 022 died during follow-up, of whom 4105 had a first degree relative with ESRD. Adjusted hazard ratio (aHR) for death was 1.13 (1.09-1.16) in individuals with a relative with ESRD compared to those without a relative with ESRD. Excluding known hereditary renal disease, aHR decreased to 1.12 (1.09-1.15). Cardiovascular death aHR was 1.15 (1.10-1.21), of which cerebrovascular death 1.34 (1.22-1.50). aHR for death due to non-hereditary renal/ureteric disease was 2.29 (1.81-2.91) with renal failure 1.80 (1.26-2.56) and glomerular disease 5.69 (3.88-8.34) as main contributors. Diabetes mellitus death aHR was 1.68 (1.35-2.10). Absolute mortality risks increased most for the oldest cohorts with excess mortality of 148 per 100.000 person years for the cohort born 1920-39 and 218 for the cohort born 1900-1919.

CONCLUSIONS

ESRD in first degree relatives was associated with increased hazard ratio for death. Death due to cardiovascular disease, renal disease and diabetes mellitus increased the most.

Risk of associated conditions in relatives of subjects with interstitial cystitis

OBJECTIVES

Urological chronic pelvic pain syndrome includes interstitial cystitis/painful bladder syndrome (IC/PBS), a chronic bladder pain condition of unknown etiology. Interstitial cystitis/painful bladder syndrome can co-occur with a number of associated conditions such as irritable bowel syndrome and fibromyalgia. The purpose of this study was to estimate the heritability of approximately 20 associated conditions in first-degree relatives (and if appropriate, second- and third-degree relatives) of patients with IC/PBS to identify shared genetic contributions for the disease combinations.

METHODS

We used the Utah Population Database, a unique population-based genealogical database that has been linked to electronic health records for the University of Utah Health Sciences Center back in 1994. Interstitial cystitis/painful bladder syndrome probands were identified by the International Classification of Diseases, Ninth Revision code for chronic interstitial cystitis and had genealogy information for 12 of their 14 immediate ancestors. We calculated excess risk of an associated condition in relatives of patients with IC/PBS using relative risk estimates.

RESULTS

We identified 248 IC/PBS probands. We found that 2 associated conditions, myalgia and myositis/unspecified (fibromyalgia) as well as constipation, were in significant excess in the patients with IC/PBS themselves, their first-degree relatives, and their second-degree relatives. The excess risk among relatives between IC/PBS and these associated conditions also held in the converse direction. Excess risk of IC/PBS was observed in the first- and second-degree relatives in probands with myalgia and myositis/unspecified (fibromyalgia) and in probands with constipation.

CONCLUSIONS

These results suggest that myalgia and myositis/unspecified (fibromyalgia) as well as constipation are likely to share underlying genetic factors with IC/PBS.

Family history of chronic renal failure is associated with malnutrition in Korean hemodialysis patients

The present study was to investigate the nutritional status and factors related to malnutrition in end-stage renal disease (ESRD) patients requiring hemodialysis (HD) in South Korea. Subjects were ESRD outpatients from general hospitals or HD centers in Seoul referred to the dialysis clinic for maintenance HD care. A total of 110 patients (46 men and 64 women; mean ages 58.6 ± 1.0 y) were eligible for this study. The family history of chronic renal failure (CRF) was considered positive if a patient reported having either a first-degree or second-degree relative with CRF. Malnutrition was defined as a triceps skinfold thickness or mid-arm muscle circumference below the fifth percentile for age and sex and forty-seven of the 110 patients were malnourished. Almost all (94%) patients had anemia (hemoglobin: <13 g/dL for men and <12 g/dL for women). Energy intake was below the recommended intake levels of energy [30-35 kcal/kg ideal body weight (IBW)] and protein (1.2 g/kg IBW) in 60% of patients. The duration of HD was longer in malnourished HD patients (P=0.0095). Malnutrition was more prevalent in women (P=0.0014), those who never smoked (P=0.0007), nondiabetic patients (P=0.0113), and patients with bone diseases (P=0.0427), adequate HD (spKt/V≥1.2) (P=0.0178), and those with a family history of CRF (P=0.0255). Multiple logistic regression was used to examine the relationship between malnutrition and potential risk factors. After adjusting for age, sex, and other putative risk factors for malnutrition, the OR for malnutrition was greater in HD patients with a family history of CRF (OR, 3.290; 95% CI, 1.003-10.793). Active nutrition monitoring is needed to improve the nutritional status of HD patients. A family history of CRF may be an independent risk factor for malnutrition in Korean HD patients. A follow-up study is needed to investigate whether there is a causal relationship between a family history of CRF and malnutrition in Korean ESRD patients.

Analysis of the association of polymorphism in the osteoprotegerin gene with susceptibility to chronic kidney disease and periodontitis

BACKGROUND AND OBJECTIVE

Chronic kidney disease (CKD) is a complex disorder, which results in several complications involving disturbance of mineral metabolism. Periodontal disease is an infectious disease that appears to be an important cause of systemic inflammation in CKD patients. Periodontal disease is characterized by clinical attachment loss (CAL) caused by alveolar bone resorption around teeth, which may lead to tooth loss. Osteoprotegerin (OPG) is a key regulator of osteoclastogenesis. Polymorphisms are the main source of genetic variation, and single nucleotide polymorphisms (SNPs) have been reported as major modulators of disease susceptibility. The aim of this study was to investigate the association of a polymorphism located at position -223 in the untranslated region of the OPG gene, previously known as -950, with susceptibility to CKD and periodontal disease.

MATERIAL AND METHODS

A sample of 224 subjects without and with CKD (in hemodialysis) was divided into groups with and without periodontal disease. The OPG polymorphism was analyzed by polymerase chain reaction and restriction fragment length polymorphism.

RESULTS

No association was found between the studied OPG polymorphism and susceptibility to CKD or periodontal disease.

CONCLUSION

It was concluded that polymorphism OPG-223 (C/T) was not associated with CKD and periodontal disease in a Brazilian population. Studies on other polymorphisms in this and other genes of the host response could help to clarify the involvement of bone metabolism mediators in the susceptibility to CKD and periodontal disease.

Evidence for a heritable predisposition to death due to influenza

Animal model studies and human epidemiological studies have shown that some infectious diseases develop primarily in individuals with an inherited predisposition. A heritable contribution to the development of severe influenza virus infection (i.e., that which results in death) has not previously been hypothesized or tested. Evidence for a heritable contribution to death due to influenza was examined using a resource consisting of a genealogy of the Utah population linked to death certificates in Utah over a period of 100 years. The relative risks of death due to influenza were estimated for the relatives of 4,855 individuals who died of influenza. Both close and distant relatives of individuals who died of influenza were shown to have a significantly increased risk of dying of influenza, consistent with a combination of shared exposure and genetic effects. These data provide strong support for a heritable contribution to predisposition to death due to influenza.

Family based studies and genetic epidemiology: theory and practice

Family based studies have underpinned many successes in uncovering the causes of monogenic and oligogenic diseases. Now research is focussing on the identification and characterisation of genes underlying common diseases and it is widely accepted that these studies will require large population based samples. Population based family study designs have the potential to facilitate the analysis of the effects of both genes and environment. These types of studies integrate the population based approaches of classic epidemiology and the methods enabling the analysis of correlations between relatives sharing both genes and environment. The extent to which such studies are feasible will depend upon population- and disease-specific factors. To review this topic, a symposium was held to present and discuss the costs, requirements and advantages of population based family study designs. This article summarises the features of the meeting held at The University of Sheffield, August 2006.

Utah family-based analysis: past, present and future

A unique genealogical resource linked to phenotype data was created in Utah over 30 years ago. Here we review the history and content of this resource. In addition, we review three current methodologies used in conjunction with this resource to define the heritable contribution to phenotypes and to identify predisposition genes responsible for these phenotypes. Example analyses and high-risk pedigrees are presented. Finally we briefly review ways this resource, or others like it, may expand in future.