BACKGROUND Hypertension is common in autosomal dominant polycystic kidney disease (ADPKD) and is associated with increased total kidney volume, activation of the renin–angiotensin–aldosterone system, and progression of kidney disease. METHODS In this double-blind, placebo-controlled trial, we randomly assigned 558 hypertensive participants with ADPKD (15 to 49 years of age, with an estimated glomerular filtration rate [GFR] >60 ml per minute per 1.73 m2 of body-surface area) to either a standard blood-pressure target (120/70 to 130/80 mm Hg) or a low blood-pressure target (95/60 to 110/75 mm Hg) and to either an angiotensin-converting–enzyme inhibitor (lisinopril) plus an angiotensin-receptor blocker (telmisartan) or lisinopril plus placebo. The primary outcome was the annual percentage change in the total kidney volume. RESULTS The annual percentage increase in total kidney volume was significantly lower in the low-blood-pressure group than in the standard-blood-pressure group (5.6% vs. 6.6%, P = 0.006), without significant differences between the lisinopril–telmisartan group and the lisinopril–placebo group. The rate of change in estimated GFR was similar in the two medication groups, with a negative slope difference in the short term in the low-blood-pressure group as compared with the standard-blood-pressure group (P<0.001) and a marginally positive slope difference in the long term (P = 0.05). The left-ventricular-mass index decreased more in the low-blood-pressure group than in the standard-blood-pressure group (−1.17 vs. −0.57 g per square meter per year, P<0.001); urinary albumin excretion was reduced by 3.77% with the low-pressure target and increased by 2.43% with the standard target (P<0.001). Dizziness and light-headedness were more common in the low-blood-pressure group than in the standard-blood-pressure group (80.7% vs. 69.4%, P = 0.002). CONCLUSIONS In early ADPKD, the combination of lisinopril and telmisartan did not significantly alter the rate of increase in total kidney volume. As compared with standard blood-pressure control, rigorous blood-pressure control was associated with a slower increase in total kidney volume, no overall change in the estimated GFR, a greater decline in the left-ventricular-mass index, and greater reduction in urinary albumin excretion.

BACKGROUND Hypertension develops early in patients with autosomal dominant polycystic kidney disease (ADPKD) and is associated with disease progression. The renin–angiotensin–aldosterone system (RAAS) is implicated in the pathogenesis of hypertension in patients with ADPKD. Dual blockade of the RAAS may circumvent compensatory mechanisms that limit the efficacy of monotherapy with an angiotensin-converting–enzyme (ACE) inhibitor or angiotensin II–receptor blocker (ARB). METHODS In this double-blind, placebo-controlled trial, we randomly assigned 486 patients, 18 to 64 years of age, with ADPKD (estimated glomerular filtration rate [GFR], 25 to 60 ml per minute per 1.73 m2 of body-surface area) to receive an ACE inhibitor (lisinopril) and placebo or lisinopril and an ARB (telmisartan), with the doses adjusted to achieve a blood pressure of 110/70 to 130/80 mm Hg. The composite primary outcome was the time to death, end-stage renal disease, or a 50% reduction from the baseline estimated GFR. Secondary outcomes included the rates of change in urinary aldosterone and albumin excretion, frequency of hospitalizations for any cause and for cardiovascular causes, incidence of pain, frequency of ADPKD-related symptoms, quality of life, and adverse study-medication effects. Patients were followed for 5 to 8 years. RESULTS There was no significant difference between the study groups in the incidence of the composite primary outcome (hazard ratio with lisinopril–telmisartan, 1.08; 95% confidence interval, 0.82 to 1.42). The two treatments controlled blood pressure and lowered urinary aldosterone excretion similarly. The rates of decline in the estimated GFR, urinary albumin excretion, and other secondary outcomes and adverse events, including hyperkalemia and acute kidney injury, were also similar in the two groups. CONCLUSIONS Monotherapy with an ACE inhibitor was associated with blood-pressure control in most patients with ADPKD and stage 3 chronic kidney disease. The addition of an ARB did not alter the decline in the estimated GFR. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; HALT-PKD [Study B] ClinicalTrials.gov number, NCT01885559.)

Breast cancer is accompanied by increased oxidative stress and induction of polymorphic cytochrome P-450 mixed oxidase enzymes (CYP). Both processes affect the abundance of volatile organic compounds (VOCs) in the breath because oxidative stress causes lipid peroxidation of polyunsaturated fatty acids in membranes, producing alkanes and methylalkanes which are catabolized by CYP. We performed a pilot study of breath VOCs, a potential new marker of disease in women with breast cancer. This was a combined case-control and cross-sectional study of women with abnormal mammograms scheduled for a breast biopsy. Breath samples were analyzed by gas chromatography and mass spectroscopy in order to determine the breath methylated alkane contour (BMAC), a three-dimensional display of the alveolar gradients (abundance in breath minus abundance in room air) of C4-C20 alkanes and monomethylated alkanes. BMACs in women with and without breast cancer were compared using forward stepwise discriminant analysis. Two hundred one breath samples were obtained from women with abnormal mammograms and biopsies read by two pathologists. There were 51 cases of breast cancer in 198 concordant biopsies. The breath test distinguished between women with breast cancer and healthy volunteers with a sensitivity of 94.1% (48/51) and a specificity of 73.8% (31/42) (cross-validated sensitivity 88.2% (45/51), specificity 73.8% (31/42)). Compared to women with abnormal mammograms and no cancer on biopsy, the breath test identified breast cancer with a sensitivity of 62.7% (32/51) and a specificity of 84.0% (42/50) (cross-validated sensitivity of 60.8% (31/51), specificity of 82.0% (41/50)). The negative predictive value (NPV) of a screening breath test for breast cancer was superior to a screening mammogram (99.93% versus 99.89%); the positive predictive value (PPV) of a screening mammogram was superior to a screening breath test (4.63% versus 1.29%). A breath test for markers of oxidative stress accurately identified women with breast cancer, with an NPV superior to a screening mammogram. This breath test could potentially be employed as a primary screen for breast cancer. Confirmatory studies in larger groups are required.

Hypertension is common and occurs in a majority of autosomal dominant polycystic kidney disease (ADPKD) patients prior to loss of kidney function. Hypertension relates to progressive kidney enlargement, and is a significant independent risk factor for progression to end stage renal disease. The pathogenesis of hypertension in ADPKD is complex and dependent on many factors that influence each other. Pkd1 and Pkd2 expression levels are highest in the major vessels and are present in the cilia of endothelial cells and in vascular smooth muscle cells. Decreased or absent polycystin 1 or 2 expression is associated with abnormal vascular structure and function. Pkd1/Pkd2 deficiency results in reduced nitric oxide (NO) levels, altered endothelial response to shear stress with attenuation in vascular relaxation. 10–20% of ADPKD children demonstrate hypertension and the majority of adults are hypertensive before any loss of kidney function. Cardiac abnormalities such as left ventricular hypertrophy and carotid intimal wall thickening are present prior to the development of hypertension in ADPKD. Activation of the renin-angiotensin-aldosterone system occurs in ADPKD due to decreased NO production as well as bilateral cyst expansion and intra-renal ischemia. With increasing cyst size, further activation of the RAAS occurs, blood pressure increases and a vicious cycle ensues with enhanced cyst growth and hypertension ultimately leading to ESRD. Inhibition of the angiotensin aldosterone system is possible with angiotensin converting enzyme inhibitors and angiotensin receptor blockers. However, interventional studies have not yet demonstrated benefit in slowing progression to renal failure in ADPKD. Currently, large multicenter studies are being performed to determine the beneficial effects of RAAS inhibition both early and late in ADPKD.

Background In people with early autosomal dominant polycystic kidney disease (ADPKD) average total kidney volume (TKV) is three times normal and increases by an average of 5% per year despite seemingly normal glomerular filtration rate (GFR). We hypothesized that increased TKV would be a source of morbidity and diminished quality of life that would be worse in subjects with more advanced disease. Study Design Cross-sectional. Setting & Participants 1043 subjects with ADPKD, hypertension and a baseline estimated glomerular filtration rate (eGFR) >20 mL/min/1.73 m2. Predictors 1) eGFR 2) height-adjusted TKV (htTKV) in subjects with eGFR >60 mL/min/1.73 m2. Outcomes 36-Item Short Form Health Survey (SF-36) and the Wisconsin Brief Pain Survey. Measurements Questionnaires were self- administered. eGFR was estimated from serum creatinine using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation. The htTKV was measured by MRI. Results Back pain was reported by 50% of subjects and 20% experienced it ‘often, usually, or always’. In subjects with early disease (eGFR >60 mL/min/1.73 m2) there was no association between pain and htTKV, except in patients with large kidneys (htTKV >1000 mL/m). Comparing across eGFR levels and including patients with eGFR <60 mL/min/ 1.73 m2, patients with eGFR 20–44 mL/min/1.73 m2 were significantly more likely to report that pain impacted on their daily lives and had lower SF-36 scores than patients with eGFR 45–60 and ≥60 mL/min/1.73 m2. Symptoms relating to abdominal fullness were reported by 20% of patients, and were significantly related with lower eGFR in women but not men. Limitations TKV and liver volume were not measured in subjects with eGFR <60 mL/min/1.73 m2. The number of patients with eGFR <30 mL/min/1.73 m2 is small. Causal inferences are limited by cross-sectional design. Conclusions Pain is a common early symptom in the course of ADPKD, although it is not related to kidney size in early disease (eGFR >60 mL/min/1.73 m2), except in individuals with large kidneys (htTKV >1000 mL/m). Symptoms relating to abdominal fullness and pain are greater in patients with more advanced (eGFR 20–45 mL/min/ 1.73 m2) disease and may be due to organ enlargement, especially in women. More research about the role of TKV in quality of life and outcomes of ADPKD patients is warranted.