Effect of Obesity on Immune Response to Pneumovax 23
Condition: Obesity
MeSH terms: Obesity
Study type: Observational

Summary: 
      Pneumococcal infections are a leading cause of adult and childhood hospitalization and death.
      It has been shown that obese individuals are at higher risk for this bacterial infection. As
      a result, investigators will vaccinate obese individuals to see if they are offered the same
      level of protection from the vaccine as normal-weight individuals. The vaccine used for this
      particular bacterial infection is called Pneumovax 23.

      The purpose of this study is to compare how body mass index affects protection that the
      vaccine provides against these bacteria.

      Primary Hypothesis: Levels of protection from the vaccine are no different in pre- and post-
      vaccination in healthy BMI individuals and obese individuals.
    

Detailed description: 
      Study Participants: For this study, the investigators will recruit 56 participants separated
      into two groups. Group 1 will enroll 23 individuals with a BMI between 22 and 25. Group 2
      will enroll 23 obese individuals. Study participants will be between the ages of 18-35 and in
      good health.

      Pre-Screening: Basic eligibility will first be determined by phone or through a
      questionnaire. The investigators will acquire weight and height information to calculate BMI,
      as well as ask about any chronic health problems. At the end of the pre-screening, an email
      address will be requested in order to email a copy of the consent form for the participant to
      review before the first visit, during which the consent form will be reviewed with the
      participant and any questions addressed. A cell phone number will also be requested to text
      participant reminders the night before their appointments (visit 1 and visit 2). If the
      participant declines a reminder text, a reminder phone call will be set-up.

      Screening: During the in-person screening, the investigators will ask several questions.
      Participants with chronic health problems (significant vascular disease, hepatitis, renal
      disease, diabetes, immunodeficiency) will be excluded. Individuals already immunized with
      Pneumovax23 or Prevnar (another vaccine that protects against pneumococcal infection) will
      also be excluded. A pregnancy test will be given to females to exclude pregnant individuals.
      An HbA1C (finger prick to get a drop of blood) will also be performed to exclude participants
      with high blood sugar levels. Physical exams will be performed and vitals will be taken on
      participants who pass the initial screening to help assess health.

      Questionnaires will also be given at the first visit to assess stress, which has been shown
      to affect the ability to protect against infection.

      Study Visits: All participants will receive a Pneumovax 23 vaccine, questionnaires, physical
      exams, and undergo 2 blood draws.

      Part of the blood will be sent to a research laboratory for gene analysis. This will help us
      determine if certain genetic markers explain individual differences in Pneumovax 23 efficacy.
    

Intervention name(s): Pneumovax 23; Blood tests; Questionnaires
Intervention type(s): Drug; Other; Other
Intervention description(s): All participants will receive a single 0.5 mL Pneumovax 23 intramuscular vaccine at baseline.; All participants will have two 50 milliliter blood draws: at baseline and up to 6 weeks later.; All participants will answer the following questionnaires:
UCLA Loneliness Scale Questionnaire will be used to measure a difference between the groups.
Perceived Stress Scale-10 Questionnaire will be used to measure a difference between the groups.
Interpersonal Support Evaluation List-12 will be used to measure a difference between the groups Life Orientation Test-Revised will be used to measure a difference between the groups.
Other intervention name(s): pneumococcal polysaccharide vaccine
Intervention MeSH terms: Heptavalent Pneumococcal Conjugate Vaccine
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Area County Adults residents with a diagnosis of Obesity who are otherwise healthy.
      
Keywords: Pneumovax23; Obesity