Salt Sensitivity Hypertension and Lens Opacities
Condition: Salt Hypertension From Excess Dietary Salt; Lens Opacities
MeSH terms: Cataract; Hypertension
Study type: Observational [Patient Registry]

Summary: 
      Salt-sensitive hypertension (SSH) accounts for about the half of all Hypertension (HT) cases
      .In SSH, Na+/K+-ATPase activity is impaired. Impaired Na+/K+-ATPase activity in the lens
      epithelium results in cortical opacities in the peripheral equator of the lens.

      This study analyzed 305 patients with hypertension aged between 40 and 80 years and 124
      non-HT controls. A total of 163 patients with HT who were admitted to the emergency service
      at least once with a minimum increase of 10% in their systolic and diastolic blood pressure
      after consuming salted food met the eligible criteria for HT and were included in the SSH
      group. A total of 142 patients who were previously diagnosed with HT but had no previous
      history were considered non-SSH. Two researchers examined the presence of cortical lens
      opacities biomicroscopically using the diffuse, direct, Scheimpflug, and retroillumination
      from fundus methods.
    

Detailed description: 
      The number of patients with hypertension (HT) worldwide is estimated to reach 1.56 billion by
      2025.HT accounts for almost 50% of deaths due to stroke and coronary artery disease.
      Salt-sensitive hypertension (SSH) accounts for about the half of all HT cases. Na+ /K+-ATPase
      activity is impaired in patients with SSH . Impaired Na+ /K+-ATPase activity in the lens
      epithelium results in cortical opacities in the peripheral equatorial region of the lens.A
      definite diagnosis of salt sensitivity is difficult, expensive, and associated with low
      patient compliance. Salt sensitivity is a risk factor for cardiovascular mortality and
      morbidity regardless of blood pressure and for other diseases such as asthma, gastric
      carcinoma, osteoporosis, and renal dysfunction. The present study is the first to investigate
      the potential of using lens opacity to predict SSH.

      The transparency of the whole lens is largely based on epithelial cell permeability and Na+
      /K+-ATPase activity. Circulation is activated by Na+ /K+-ATPases, which are present at
      20-fold normal concentrations, particularly in the equatorial than in the anterior epithelial
      cells.

      The mechanisms associated with SSH pathogenesis, such as signaling pathways involving Src
      family kinase (SFK), endothelin, connexin, brain natriuretic peptide (BNP), aldosterone,
      transient receptor protein V4 (TRPV4) ion channel, with-no-lysine kinase-Ste20-like
      proline/alanine rich kinase/oxidative stress-responsive kinase 1 (WNK-SPAK/OSR1), and
      Ras-related C3 botulinum toxin substrate (Rac1) , are important to the physiology of the lens
      epithelium. Compelling studies suggest that inhibition of these pathways may facilitate
      opacity.
    

Intervention name(s): Lens examination
Intervention type(s): Diagnostic Test
Intervention description(s): The presence of cortical lens opacity was biomicroscopically examined by two researchers using the diffuse, direct, Scheimpflug and retroillumination from the fundus methods.
Other intervention name(s): urine analysis for salt intake; Blood pressure measurements
Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Probability Sample
Study population: 
        The HT and control groups were subdivided into age groups of < 50, 50-59, 60-69, and ≥ 70
        years. These age groups comprised 54, 109, 80, and 62 patients in the HT group and 19, 42,
        42, and 21 patients in the control group, respectively.