title: Incidence of hypertension in individuals with different blood pressure salt-sensitivity: results of a 15-year follow-up study.
abstract: OBJECTIVE
  To evaluate the incidence of hypertension and the rate of decline in renal function in a sample of 47 Olivetti Heart Study (OHS) participants whose blood pressure (BP) salt-sensitivity and renal tubular sodium handling had been assessed in 1987-88.
  
  
  METHODS
  During the 2002-04 OHS follow-up examination, medical history, physical examination and blood and urine sampling were performed in 36 of the 47 participants to the baseline study (age 60 +/- 6 years; average follow-up = 15.1 +/- 0.6 years). The renal length was measured in 23 participants by kidney ultrasonography. Based on the baseline salt-sensitivity evaluation, the subjects were classified into a lower salt-sensitivity (LSS, n = 20) and a higher salt-sensitivity group (HSS, n = 16).
  
  
  RESULTS
  In comparison with the LSS group, HSS participants had a significantly higher incidence of hypertension (87.5 versus 50.0%, P = 0.02), a higher glomerular filtration rate (median, first to fourth quartile: 81.9, 72.3-95.2 versus 72.3, 59.9-81.2 ml/min; P = 0.03) and greater kidney length (median, first to fourth quartile: 68.2, 63.3-72.1 versus 61.9, 58.7-62.7 mm/m of height; P = 0.003). The incidence of hypertension remained significantly higher in HSS individuals after adjustment for age, intercurrent changes in body mass index and baseline blood pressure on low sodium diet (P = 0.04).
  
  
  CONCLUSIONS
  Our findings indicate that individuals with higher BP salt-sensitivity have a higher rate of incident hypertension and suggest an altered renal tubular sodium handling involving a trend to increased glomerular filtration rate and blood pressure over time as a possible mechanism.
authors.affiliation: Epidemiology and Population Genetics, Institute of Food Sciences, CNR, Avellino, Italy. gbarba@isa.cnr.it
authors.forename: Gianvincenzo
authors.initials: G
authors.lastname: Barba
authors.forename: Ferruccio
authors.initials: F
authors.lastname: Galletti
authors.forename: Francesco P
authors.initials: FP
authors.lastname: Cappuccio
authors.forename: Alfonso
authors.initials: A
authors.lastname: Siani
authors.forename: Antonella
authors.initials: A
authors.lastname: Venezia
authors.forename: Marco
authors.initials: M
authors.lastname: Versiero
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Della Valle
authors.forename: Paolo
authors.initials: P
authors.lastname: Sorrentino
authors.forename: Giovanni
authors.initials: G
authors.lastname: Tarantino
authors.forename: Eduardo
authors.initials: E
authors.lastname: Farinaro
authors.forename: Pasquale
authors.initials: P
authors.lastname: Strazzullo
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000139:chemically induced / Q000453:epidemiology* / Q000503:physiopathology; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D007668:Kidney / Q000000981:diagnostic imaging / Q000502:physiology; D008297:Male; D008875:Middle Aged; D017673:Sodium Chloride, Dietary / Q000009:adverse effects*; D014463:Ultrasonography
chemical_list: D017673:Sodium Chloride, Dietary