Study of Cobalt's Role in Excessive Erythrocytosis Among High Altitude Dwellers in Cerro de Pasco, Peru

Phase 1

Completed

• Conditions: Mountain Sickness; Erythrocytosis
• Interventions: Drug: Placebo pills; Drug: N-acetylcysteine; Drug: Acetazolamide

• Registration Number: NCT01187108
• Lead Sponsor: University of Colorado, Denver

Brief Summary

Chronic mountain sickness is characterized by excessive red blood cell production which causes sludging of the vascular system. This high viscosity blood causes heart failure, cognitive dysfunction, and strokes. The investigators hypothesize that cobalt which has been previously been shown to be an environmental pollutant worsens the overproduction of red blood cells. The investigators plan to conduct a 6 week trial in which acetazolamide (already shown to improve chronic mountain sickness) and N-acetylcysteine (a drug that removes cobalt from the blood) are evaluated in their potential to improve chronic mountain sickness.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2010-08-18
• Study First Submitted QC: 2010-08-20
• Study First Posted: 2010-08-23
• Study Start: 2013-06
• Primary Completion: 2013-09
• Study Completion: 2013-09
• Status Verified: 2015-05
• Last Update Submitted: 2015-05-13
• Last Update Posted: 2015-05-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 85

Inclusion Criteria

• Males over 17 years of age
• Hematocrit > 70%
• Chronic Mountain Sickness score (CMS) > 6
• Able to give informed consent and follow instructions in written Spanish

Exclusion Criteria

• CMS > 15
• Underlying lung disease, smoking, or oxygen therapy
• Asthma (bronchospasm can be caused by N-acetylcysteine)
• Phlebotomy in last 3 months
• h/o adverse reaction to acetazolamide or N-acetylcysteine

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: FACTORIAL

Arm && Interventions

Group	Intervention	Description
Combination of N-acetylcysteine and acetazolamide	Acetazolamide	-
Placebo pills	Placebo pills	-
N-acetylcysteine alone	Placebo pills	-
Acetazolamide alone	Acetazolamide	-
N-acetylcysteine alone	N-acetylcysteine	-
Acetazolamide alone	Placebo pills	-
Combination of N-acetylcysteine and acetazolamide	N-acetylcysteine	-

Primary Outcome Measures

Name	Time	Method
Change from baseline in Hematocrit, or fraction of plasma occupied by cellular elements at week 8	Baseline and week 8	Spun hematocrit measured on portable machine

Secondary Outcome Measures

Name	Time	Method
Change from baseline in arterial blood gas values at week 8	Baseline and week 8	Analyzed using portable machine. The values analyzed include serum pH, partial pressure of carbon dioxide, partial pressure of oxygen, and serum bicarbonate.
Change in baseline urine protein at 8 weeks	Baseline and week 8	Ratio of urine total protein to urine creatinine
Change in baseline Chronic mountain sickness score at 8 weeks	Baseline and week 8	Chronic Mountain Sickness Score Absent Mild Moderate Severe Headache 0 +1 +2 +3 Dizziness 0 +1 +2 +3 Failing Memory 0 +1 +2 +3 Fatigue 0 +1 +2 +3 Breathlessness 0 +1 +2 +3 Sleep disturbances 0 +1 +2 +3 Tinnitus 0 +1 +2 +3 Anorexia 0 +1 +2 +3 Cyanosis of lips, face, or fingers 0 +1 +2 +3 Hyperemia or prominent capillaries conjunctivae or laryngopharynx 0 +1 +2 +3
Change from baseline Erythropoietin at week 8	Baseline and week 8	Serum hormone that stimulates red blood cell production
Change from baseline in serum and urine Cobalt at day 3	Baseline and day 3	Will calculate spot clearance of cobalt
Changes in baseline Serum electrolytes at day 3, 14 and week 8	Baseline and Days 3, 14, and week 8	Electrolytes, specifically monitoring serum potassium to treat serious hypokalemia (serum potassium \< 3.0 meQ/L).

Trial Locations

Locations (1)

Chronic mountain sickness clinic; 🇵🇪 Cerro de Pasco, Pasco, Peru