Hypertension Treatment in Nigeria: Hypertension Diabetes Integration Study- Formative Aim 3 (HTN2)

Experimental: Primary Health Care Centers in the Federal Capital Territory

10 primary healthcare centers in Nigeria's Federal Capital Territory who previously demonstrated capacity to deliver hypertension care in HTN 1.0.

Otro: Implementation of program based on WHO HEARTS-D guidelines

This study uses an interrupted time series design to compare diabetes screening, diagnosis, treatment, and control across a 12-month pre-implementation period and a 24-month implementation period in 10 primary healthcare centers in Nigeria's Federal Capital Territory. Sites previously demonstrated capacity to deliver hypertension care and will continue hypertension services while expanding to diabetes care through the HEARTS diabetes module (HEARTS-D). Pre-implementation includes registry setup and provision of glucometers without diabetes treatment training. Implementation includes HEARTS-D training, supply provision, expansion of the drug revolving fund to diabetes medicines, and quarterly supportive supervision.

Droga: Metformin

Description: Oral biguanide used as first-line glucose-lowering therapy within the HEARTS-D stepped-care protocol. Dosing per protocol: 500 mg once daily (Step 1), 1000 mg once daily (Step 2), 1000 mg twice daily (Step 3 and Step 4). Supplied through the expanded drug revolving fund during the implementation period.

Droga: Glimepiride

Oral sulfonylurea used as add-on therapy at Step 4 of the HEARTS-D stepped-care protocol when blood glucose remains uncontrolled on metformin. Starting dose 1 mg once daily, titrated by 1-2 mg to a maximum of 8 mg daily. Supplied through the expanded drug revolving fund during the implementation period.

Dispositivo: Point-of-care blood glucose monitor (glucometer) and compatible test strips

Point-of-care capillary blood glucose monitor with compatible single-use test strips and lancets, used at participating primary health centers for diabetes screening, diagnosis, and monitoring per WHO HEARTS-D. Glucometers and test strips are provided to all sites during pre-implementation (registry setup) and replenished during implementation through the supply chain and drug revolving fund.

Otros nombres:

• Capillary blood glucose meter
• finger-stick glucose meter

Conductual: HEARTS-D training and quarterly supportive supervision for community health extension workers (CHEWs)

Structured training of CHEWs on the HEARTS-D protocol covering diabetes screening, diagnosis, stepped-care treatment, follow-up, and referral, delivered at the start of the implementation period and reinforced by quarterly supportive supervision visits with audit-and-feedback throughout the 24-month implementation period.

Otros nombres:

• Provider training
• Supportive supervision

Dose of quarterly supportive supervision visits measured by the proportion of observed/expected visits during the implementation period.

Primary Implementation Outcome: Description: Dose of quarterly supportive supervision visits measured by the proportion of observed/expected visits during the implementation period.

Difference in 6-month rolling average diabetes screening in eligible adults (random plasma glucose with hyperglycemia symptoms; fasting plasma glucose if ≥18 y and BMI >25 kg/m²; or HbA1c) per WHO HEARTS-D, pre- vs. implementation

Primary effectiveness outcome: The primary outcome will be the difference in the 6-month rolling average of the diabetes screening among eligible patients, screening defined as a random plasma glucose screening among adults with symptoms of hyperglycemia or a fasting plasma glucose among adults > 18 years old and body mass index > 25 kg/m2 in accordance with HEARTS-D, between the pre-implementation and implementation periods. Hemoglobin A1c may also be used if available.

Difference in 6-month rolling average diabetes treatment (proportion of eligible patients prescribed any glucose-lowering medication) between pre-implementation and implementation periods

Secondary Effectiveness Outcome (diabetes treatment): 6-month rolling average of diabetes treatment levels in the pre-implementation and implementation periods.

Difference in 6-month rolling average blood sugar control (per WHO HEARTS-D: fasting plasma glucose <126 mg/dL, postprandial <160 mg/dL, or HbA1c <7%) between pre-implementation and implementation periods

Secondary Effectiveness Outcome (blood sugar control): 6-month rolling average of blood sugar control in the pre-implementation and implementation periods. Control will be defined according to the WHO HEARTS-D module2, specifically: fasting glucose <126 mg/dl, postprandial glucose <160 mg/dl, or HbA1c <7%.

Difference in 6-month rolling average mean fasting plasma glucose (mg/dL) between pre-implementation and implementation periods

Secondary Effectiveness Outcomes (mean fasting glucose levels): 6-month rolling average of mean fasting glucose levels in the pre-implementation and implementation periods.

Proportion of selected primary health centers (PHCs) that participated in baseline diabetes training (A ÷ B; A = PHCs that participated, B = total selected PHCs)

Secondary Implementation Outcome:

A = Number of PHCs who participated in baseline diabetes training B = Total number of selected PHCs

Calculation: A ÷ B

Proportion of selected PHCs that received at least one supportive supervision visit in the past 12 months (A ÷ B; B = total selected PHCs)

Secondary Implementation Outcome:

A = Number of PHCs who received at least one supportive supervision visit in the past 12 months B = Total number of selected PHCs

Calculation: A ÷ B

Proportion of eligible PHCs that received at least one audit-and-feedback report within the past 3 months (A ÷ B)

Secondary Implementation Outcome:

A = Number of PHCs who received at least an audit and feedback report within the past 3-months B = Total number of selected PHCs

Calculation: A ÷ B

Percentage of PHCs with a working blood glucose monitor on-site on the day of assessment (last supervision visit) (A ÷ B)

Secondary Implementation Outcome:

A = Number of PHCs with a working blood glucose monitor at the site on the day of assessment (time point: last supervision visit) B = Total number of selected PHCs

Calculation: A ÷ B

Percentage of PHCs with diabetes medicines available on-site on the day of assessment (last supervision visit) (A ÷ B)

Secondary Implementation Outcome:

A = Number of PHCs with diabetes medicines available on the day of assessment (time point: last supervision visit) B = Total number of selected PHCs

Calculation: A ÷ B

6-monthly rolling average percentage of registered diabetes patients with clinically indicated step-up who received step-up treatment within 6 months (A = patients needing and receiving step-up; B = patients registered per month)

Secondary Implementation Outcome:

A = Number of patients who need step up treatment and received it

B = Total number of patients who are registered per month

Calculation: A ÷ B, 6-monthly rolling average rate

6-monthly rolling average monthly proportion of registered diabetes patients receiving appropriate stepped care, out of total registered patients (A ÷ B)

Secondary Implementation Outcome:

A = Number of patients who need step up treatment and received it

B = Total number of patients who are registered per month

Calculation: A ÷ B, 6-monthly rolling average rate

Difference in the proportion of patients with serious adverse events (SAEs) between pre-implementation and implementation periods

Safety Outcome: between-period (pre-implementation versus implementation) differences in proportions of serious adverse events

Difference in the proportion of patients with adverse events of special interest (hypoglycemia, hyperglycemia, medication allergies, common medication side effects) between pre-implementation and implementation periods

Safety Outcome: e.g., hypoglycemia, hyperglycemia, medication allergies, common medication side effects in pre-implementation and implementation periods.