HF: Thiamine (2007)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:

To assess the prevalence of thiamine deficiency in elderly hospital inpatients with cardiac failure and the effect of thiamine treatment on the cardiac failure course.

Inclusion Criteria:

Cardiac failure, based on clinical signs of left and right ventricular failure, supported by radiographic evidence of cardiac lung.

Exclusion Criteria:
  • Alcohol abuse and use of vitamins prior to admission
  • Control patients for thiamine status: Any history or clinical or radiological signs of heart disease.
Description of Study Protocol:
  • Recruitment: Patients admitted to the Department of Geriatric Medicine of the University Hospital of Dijon between August 1990 and September 1991
  • Design: RCT.

Intervention (if applicable)

  • A baseline assessment of thiamine status was performed on all 70 patients (35 with heart failure and 35 without). Then those who had cardiac failure (N=35) were randomized into either the thiamine-supplemented group (CF1) or the non-supplemented group (CF2)
  • 200mg intravenous or intramuscular thiamine per day was given to CF1 for seven days
  • Biochemical thiamine assessment was performed on Day Eight, while the clinical and roentgenological assessment was made on both Days Eight and 15.

Statistical Analysis

All data were determined not to be normally distributed. Therefore, quantitative variables were transormed into semi-quantitative variables of the type (low or high) and groups were compared by a Chi-square test for all the variables.

Data Collection Summary:

Timing of Measurements

  • Day Zero (within 24 hours of admission): For estimation of thiamine status and for the clinical assessment and chest roentgenogram for cardiac function in all patients
  • Day Eight: Biochemical thiamine assessment, clinical assessment and chest roentgenograms in the cardiac failure patients
  • Day 15: Clinical assessment and chest roentgenograms in the cardiac failure patients.

Dependent Variables

  • Variable One (thiamine status)
    • Blood was sampled by venipuncture into an heparinized Venoject evacuated tube
    • The samples were kept in crushed ice
    • Plasma was removed after centrifugation at 1,000xg for 10 minutes at 4°C and the erythrocytes were washed three times with an equal volume of saline
    • Erythrocyte transketolase (ETK) activity and the thiamine pyrophosphate (TPP) stimulation effect (TPPE) were determined by the method of Smeets
    • ETK activity was expressed in International Units (IU) per liter of sample, equivalent to the number of micromoles of glyceraldehyde-3-P formed per minute per liter
    • Erythrocyte TPP was measured using the high-performance liquid chromatography (HLPC) Warnocke method
    • Values lower than 230IU for basal ETK, higher than 1.19 for TPPE and lower than 0.17µmol, 1–1 for erythrocyte TPP were considered as deficient.
  • Variable Two: Clinical assessment included body weight, diuresis, heart rate and blood pressure and breathlessness and edema assessment. Radiologic signs were assessed by chest roentgenograms.

Independent Variable

200mg thiamine given IV or IM.

Description of Actual Data Sample:

 

Initial N

  • 70 (11 males, 24 women in HF group
  • Not specified for the control group except that they were "strictly matched by sex and age for assessment of thiamine status"
  • 35 for the effect of thiamine treatment on cardiac failure.

Attrition (final N)

Same as initial.

Age

76-95 years (mean 86±3.3).

Ethnicity

Not stated.

Other Relevant Demographics

  • Anthropometrics
    • Heart failure was due to systemic hypertension in 61%, coronary arterial disease in 50% (often a combination of both) and valvular disease in 18%
    • The cardio-thoracic value was ²0.50 (mean 0.63±0.04) and an upper zone flow redistribution was noted
    • Alveolar pulmonary edema, interstitial pulmonary edema and pleural effusions were observed in 28%, 34% and 23% of the cases, respectively
    • All patients were classified in the NYHA as either Class Three or Four.
  • The patients were receiving combination therapy including digoxin, nitrates, ACE inhibitors and furosemide
  • Twenty patients underwent long-term pre-admission furosemide therapy (doses 20mg to 40mg/j)
  • Non heart failure patients had altered cognitive function of psychiatric disorders in 15, infection in eight, syncope and fall in eight, cancer in three and iatrogenic disease in one. 

Location

Dijon, France.

Summary of Results:

Variables

 

Treatment Group
Measures and Confidence Intervals

Control Group
Measures and Confidence Intervals

Statistical Significance of Group Difference

Dependent Variable One

Cardiac failure (CF)

Non-cardiac Failure (non-CF)

Statistically significant difference between groups

 

Basal ETK (IU)

281±93

291±101

NS: 28.5% in each group were deficient (NL>230)  

 

TPPE

1.11±0.07

1.11±0.05

NS: 11.5% of CF and 6% of non-CF deficient (NL<1.19)

 

CF1 (baseline, vitamin supplement)

CF2 (baseline, no supplement)

 

 

Basal ETK (IU)

279±103

288±93

NS

 

TPPE

1.12±0.06

1.10±0.06

NS

 

Erythrocyte TPP (µmol.1-1

0.19±0.04

0.20±0.05

NS

Dependent Variable Two

CF1 (baseline, vitamin supplement); Day Eight

CF2 (baseline, no supplement); Day Eight

 

 

Basal ETK (IU)

345±112 (6% deficient)

277±54 (33% deficient)

P=0.009

 

TPPE

1.10±0.06 (0% deficient)

1.08±0.07 (6% deficient)

P=0.015

 

Erythrocyte TPP (µmol.1-1

0.45±0.32 (6% deficient)

0.43±0.29 (47% deficient)

P=0.026

Other Findings

  • Deficiency in baseline ETK, TPPE and erythrocyte TPP was more frequent in patients with Class Four NYHA vs. those in Class Three. However, it was not a significant difference. There also was no statistical difference between the furosemide-treated group and the non-treated group for these parameters. 
  • At Day 15, there was improvement in clinical symptoms in 94% of the untreated group and in 65% of the treated group, but this was not a statistically significant difference (P=0.072). There was no significant improvement in the cardiothoracic value of either group. There was also no difference in the two groups in medications used
  • No adverse events were mentioned.
Author Conclusion:
  • A significant improvement in thiamine status was noted. However, there was no clinical improvement, compared to controls.
  • Whether systematic thiamine supplementation is indicated in cardiac failure patients requires further studies.

 

Funding Source:
University/Hospital: Universitaire De Dijon
Reviewer Comments:
  • Small number of patients
  • Comparison group for baseline thiamine status was also comprised of ill patients, even though the mean values were normal. Perhaps a group with healthy individuals might have had a smaller percentage who were deficient.
  • No explanation was given for the use of either IV or IM thiamine in the experimental group.
Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
 
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) No
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) Yes
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? N/A
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? N/A
  4.1. Were follow-up methods described and the same for all groups? N/A
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) N/A
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? N/A
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? ???
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? ???
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) ???
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? Yes
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? N/A
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? N/A
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? ???
  10.1. Were sources of funding and investigators' affiliations described? No
  10.2. Was the study free from apparent conflict of interest? ???