Lysine Trial in Adults With Diarrhoea
Condition: Diarrhea
MeSH terms: Diarrhea
Study type: Interventional

Summary: 
      Diarrhea as of today is still a major problem in developing world with high morbidity. Though
      mortality in under-5 children has declined over the years, diarrhea was responsible for 2.5
      million deaths per year in developing countries. A median of 3.2 episodes of diarrhea in
      under-5 children per child-year has been estimated in developing countries. In Bangladesh,
      the overall prevalence of diarrhea was estimated to be about 2% for the entire population.
      However, a recent survey in 2003 with urban slum mothers indicated that the prevalence of
      diarrhea ranged from 0.7-4.1% in six divisional cities with 0.7% in Dhaka slum areas.
      Malnutrition remains the major adverse prognostic indicator for diarrhea related morbidity,
      which emphasizes importance of nutrition in early management. Repeated episodes of diarrhea
      are a frequent cause and consequence of malnutrition. To improve diarrhea situation in
      Bangladesh and elsewhere, interventions are directed to reduce mortality and morbidity
      through improvement of breast-feeding practices, complementary feeding, sanitation, increase
      in measles immunization rates, micronutrient supplementation, and oral rehydration therapy.

      L-lysine, an essential amino acid, is required for healthy growth, tissue repair and enzyme
      production. It is a protein-building block that strengthens and nourishes the structural,
      circulatory and immune systems. It is not produced by the body like other essential amino
      acids and must be obtained from the diet. Some natural food sources for L-lysine include Lima
      beans, kidney beans, potatoes, corn, red meat, fish and milk. The mean requirement of lysine
      in healthy human adults is about 30 mg/kg body weight/day or 50 mg/g protein intake. Studies
      have shown that lysine therapy improves immune status and is used as a therapeutic agent in
      herpes simplex viral infection. A double-blind randomized trial of L-lysine treatment found
      it to be an effective agent for significant reduction in occurrence, severity and healing
      time for recurrent herpes simplex viral infection. Lysine fortification increased the blood
      levels of complement 3 (C3), CD-4 and CD-8 T-cells as compared with controls. These two
      studies suggest that supplementation of lysine through food fortification enhances
      immunological status. A few recent studies have also shown an effect of lysine on diarrheal
      incidence and severity. An experimental model suggested inhibitory effect of L-lysine on
      incidence of diarrhea induced by stress and 5-hydroxytryptamine. A community trial among
      adults in Syria showed that the period prevalence and mean duration of diarrheal illness were
      significantly lower in the female participants who consumed lysine-fortified wheat bread
      compared to the control group as well as better immunological parameters such as C3c delta.

      The proposed study will observe the impact of a daily dose of 2000 mg supplemental L-lysine
      for 6 months on diarrheal illness in an adult population of an urban slum area in Dhaka whose
      principal diet is based on cereals such as rice and or wheat. The daily protein and lysine
      availability from diets of Bangladeshi population has been calculated to be about 43g and
      1883 mg respectively, compared to 113g and 7,598 mg respectively in the USA. This means that
      2000 mg daily supplementation of L-lysine would not pose any detrimental effect, as the
      combined usual and supplemental intake will still be substantially lower compared to the
      intake in USA. However, as expected, the supplemental L-lysine may reduce the incidence and
      severity of diarrheal illness through improvement of the nutritional and immunological status
      of the study population.

      The investigators propose to conduct a community-based, double-blind randomized controlled
      trial in Mirpur area of Dhaka city. Adults aged 18 to 45 years residing in the catchment area
      for at least the last six months will be eligible for the study. A total of 440 subjects (220
      females) will be enrolled. The results of the proposed study will contribute to our existing
      knowledge of the effect of lysine on incidence and severity of diarrheal illness as well as
      on immune status. A positive impact of lysine supplementation on diarrheal illness may lead
      to a future strategic approach to the control of diarrhea as a global public health problem.
    


Intervention name(s): lysine supplementation; Placebo
Intervention type(s): Dietary Supplement; Dietary Supplement
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Diarrhea; L-lysine supplementation; immune status; adults; Bangladesh; aged 18-45 years; urban community