Effects of a Supplement on Acute Respiratory Infections
Condition: Respiratory Tract Infection
MeSH terms: Infections; Communicable Diseases; Respiratory Tract Infections
Study type: Interventional

Summary: 
      The purpose of this study is to determine whether the consumption of a nutritional supplement
      with micronutrients and herbal extracts has an effect on the incidence of acute respiratory
      infections in susceptible adults.

      Our hypothesis is that subjects who consume the nutritional supplement will have a lower
      incidence and duration of acute respiratory infections in comparison with the placebo group.
    

Detailed description: 
      We conducted a randomized, parallel, double-blind, placebo-controlled, 90-day clinical trial
      from January to April, 2012. All staff who worked at the Omnilife's Entrepreneur Support
      Department (CREO by its initials in Spanish) were invited to participate. This department
      within Omnilife has a high incidence of acute respiratory infections (ARI) as reported
      internally by the company's medical service (accounting for 55% of doctor visits within the
      department in 2010) and hence, they represent a high number of individuals susceptible to
      ARI.

      We held a preliminary session with the department's entire staff to explain the procedures;
      we asked subjects interested to participate in the study to sign an informed consent form and
      fill a clinical history. The latter included an assessment of stress, using the Perceived
      Stress Scale (in which higher scores indicate higher levels of stress), and physical
      activity, using the International Physical Activity Questionnaire or IPAQ (in which physical
      activity is categorized in three levels: light, moderate and vigorous).

      In a second session the same week, participants visited the company's medical service for
      measurements of their weight and height (in accordance with the International Society for the
      Advancement of Kinanthropometry or ISAK standards), control laboratory tests and a medical
      examination to rule out the presence of infections. Weight measurements were taken using a
      Tanita BC553 Ironman Inner Scan Body Fat Scale (capacity of 150 kg, accuracy to 0.1 kg).
      Height measurements were made using a Seca 206 Stadiometer (accuracy to 0.1 cm, measuring
      range to 220 cm). Both measurements were performed by a two certified and standardized
      anthropometrists. Body mass index (BMI) was subsequently calculated using both variables as
      follows: BMI = weight in kg/(height in m)2.

      The medical examination was performed by the attending physician and a nurse. It consisted of
      an assessment of vital signs following procedures described in the literature and a physical
      examination of bodily organs and systems. Temperature was measured using a Microlife MT 1931
      digital thermometer (measuring range from 32 to 43.9°C, accuracy to 0.1°C). Heart and
      respiratory rates were measured using a 3M Littmann Classic II S.E. stethoscope. Blood
      pressure readings were taken using a 3M Littmann Classic II S.E. stethoscope and an Aneroid
      Sphygmomanometer ce0483 (18-300 mmHg measurement range, accuracy to 2 mmHg).

      Laboratory tests were conducted with the support of an external laboratory (Instituto
      Diagnostico Especializado Arboledas, IDEA by its initials in Spanish). Included were a blood
      test of six items (fasting glucose, uric acid, creatinine, blood urea nitrogen, cholesterol
      and triglycerides) analyzed by the spectrophotometric method, a complete blood count with a
      flow cytometry/microscopy analysis of platelets, and a spectroscopy analysis to assess liver
      function. Subjects of laboratory analyses were tested after a 12-hour fast. This laboratory
      has obtained quality control certification from the Quality Assurance for Laboratories
      Program (PACAL) and the Internal Evaluation Quality Program (PREVECAL). In addition, its
      staff is certified in clinical diagnosis by the National Association of Clinical Chemists
      (CONAQUIC).

      Subjects who met inclusion criteria were randomly assigned to two groups: one which received
      the supplement (n=30), and a control group who received a placebo, which consisted in a
      mixture of maltodextrins, colors and flavors. Every day two dietitians prepared the products,
      who then gave the prepared products to two different supervisors who in turn gave the product
      to each participant for consumption. The supervisors recorded product administration and
      consumption for each participant on a control form.

      Simultaneously, each week the supervisors provided each participant with an ARI symptom and
      side effect diary to be filled in daily (indicating whether or not the symptom in question
      had presented). Participants delivered the supervisors their filled-in diaries the following
      week. Subjects were also requested not to self-medicate in the event they should feel any of
      the symptoms and to notify the principal researcher and attending physician, who would make a
      clinical assessment to confirm the presence or absence of ARI and provide any needed medical
      treatment. In such cases, participants were not to be excluded from the study, but treatment
      provided to them was documented. At the end of the supplementation period, the initial
      assessments were performed again. Subjects were also asked about their perceptions of their
      own health at that time compared to how they felt at the beginning of the study.

      Quantitative variables are expressed as mean (SD). Qualitative variables are expressed as
      frequency (%). Fisher's exact test was used to compare distribution percentages of
      qualitative variables between groups and to compare the total proportion of ill subjects
      across intervention groups using intent-to-treat and per-population concepts. The risk ratio
      and the risk difference were also calculated for episodes of ARI. To compare the average of
      quantitative variables between treatments, the Mann-Whitney U test was used. Statistical
      analyzes were run using the SPSS program version 10 for Windows and Open Epi version 3.01;
      p<0.05 was considered as significant.
    

Intervention name(s): Omniplus Supreme; Placebo
Intervention type(s): Dietary Supplement; Other
Intervention description(s): Two dietitians prepared the products (one preparer per product) by dissolving two envelopes of 20 ml of the product in 240 ml of water in a disposable cup, every day from Monday to Saturday during the intervention period (90 days of actual consumption). In order to maintain blinding, these dietitians then gave the prepared cups to two different supervisors who in turn gave the product to each participant for consumption (once-daily doses). The preparation and delivery of the product was carried out during two work shifts (morning and afternoon), depending on each participants work schedule. The supervisors recorded product administration and consumption for each participant on a control form.; A product with maltodextrins, flavors and colorants without vitamins, minerals and plant extracts. Two dietitians prepared the products (one preparer per product) by dissolving two envelopes of 20 ml of the product in 240 ml of water in a disposable cup, every day from Monday to Saturday during the intervention period (90 days of actual consumption). In order to maintain blinding, these dietitians then gave the prepared cups to two different supervisors who in turn gave the product to each participant for consumption (once-daily doses). The preparation and delivery of the product was carried out during two work shifts (morning and afternoon), depending on each participants work schedule. The supervisors recorded product administration and consumption for each participant on a control form.
Other intervention name(s): Food supplement with micronutrients and plant extracts
Intervention MeSH terms: Micronutrients
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Prevention
Keywords: Respiratory tract infection; Incidence; Dietary supplements; Micronutrients; Plant extracts