with engine.connect() as conn:
    df = pd.read_sql("""
        SELECT TOP 20
               s.PROCHI,
               d.sex,
               d.Calculated_Age,
               COUNT(*) AS TotalAdmissions,
               SUM(s.LENGTH_OF_STAY) AS TotalDays
        FROM Project_12345..SMR01_Admissions s
        INNER JOIN Project_12345..Demography_Current d
            ON s.PROCHI = d.PROCHI
        GROUP BY s.PROCHI, d.sex, d.Calculated_Age
        ORDER BY TotalAdmissions DESC
    """, conn)

df

df <- dbGetQuery(conn, "
    SELECT TOP 20
           s.PROCHI,
           d.sex,
           d.Calculated_Age,
           COUNT(*) AS TotalAdmissions,
           SUM(s.LENGTH_OF_STAY) AS TotalDays
    FROM Project_12345..SMR01_Admissions s
    INNER JOIN Project_12345..Demography_Current d
        ON s.PROCHI = d.PROCHI
    GROUP BY s.PROCHI, d.sex, d.Calculated_Age
    ORDER BY TotalAdmissions DESC
")

df